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Trace Minerals Flashcards

1
Q

What is the most abundant trace element in the body?

A

Iron (Fe)

Iron plays a crucial role in various biological functions.

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2
Q

What is the most common nutrient deficiency in the world?

A

Iron deficiency anaemia

This condition affects a significant portion of the global population.

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3
Q

How much iron do adults contain in grams?

A

Between 2.5-4 g (0.01% of body weight)

The amount can vary based on individual health and diet.

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4
Q

What percentage of iron in the body is found in the form of haemoglobin?

A

60%

Haemoglobin is vital for oxygen transport in the blood.

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5
Q

What percentage of iron is found as myoglobin?

A

5%

Myoglobin helps in oxygen storage in muscle tissues.

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6
Q

What is the role of enzymes in relation to iron?

A

5% of iron is part of enzymes

Enzymes facilitate various biochemical reactions in the body.

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7
Q

What are the other forms of iron found in the body aside from haemoglobin and myoglobin?

A

Blood and storage (ferritin)

Ferritin serves as a storage form of iron.

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8
Q

Fill in the blank: Iron is the _____ most abundant mineral in the earth’s crust.

A

fourth

The most abundant minerals are Oxygen, Silicon, and Aluminium.

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9
Q

What is the chemical symbol for iron?

A

Fe

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10
Q

Iron is classified as what type of metal?

A

Transition metal

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11
Q

What are the two most stable oxidation states of iron?

A
  • Ferric (Fe3+) * Ferrous (Fe2+)
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12
Q

What essential role does iron play in biological systems?

A

Essential for oxidation-reduction reactions

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13
Q

What is a special property of iron regarding its oxidation states?

A

Easily changing between two oxidation states

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14
Q

What is the reduced form of iron commonly found in foods?

A

Ferrous (Fe2+)

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15
Q

What is the oxidized form of iron that is able to bind to transferrin?

A

Ferric (Fe3+)

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16
Q

In what type of conditions is ferric iron soluble?

A

Low pH conditions

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17
Q

In what type of conditions is ferrous iron soluble?

A

Neutral to high pH conditions

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18
Q

What is a potential negative consequence of free iron in biological systems?

A

Ability to promote formation of free radicals

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19
Q

Fill in the blank: Free iron can lead to free radicals formation → need to be in _______ form.

A

Complex

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20
Q

True or False: Iron can only exist in one oxidation state.

A

False

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21
Q

What is the primary function of haemoglobin?

A

Carries oxygen in blood

Haemoglobin is a protein in red blood cells that transports oxygen from the lungs to the rest of the body.

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22
Q

What role does myoglobin play in the body?

A

Resides in muscle and moves oxygen into muscle cells

Myoglobin is a protein that helps store and release oxygen in muscle tissues.

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23
Q

What element is at the center of the haem protein?

A

Iron

Iron is crucial for oxygen binding in both haemoglobin and myoglobin.

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24
Q

Fill in the blank: Iron is the _______ containing portion of haemoglobin and myoglobin.

A

iron

The presence of iron is essential for the oxygen-carrying capacity of these proteins.

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25
True or False: Myoglobin is found in blood.
False ## Footnote Myoglobin is located in muscle tissue, not in blood.
26
What does haemoglobin transport?
Oxygen ## Footnote Haemoglobin is specifically designed to bind oxygen molecules for transport.
27
What is the relationship between haemoglobin and myoglobin?
Both are haem proteins that bind oxygen ## Footnote While they have similar functions, they are found in different locations in the body.
28
What are cytochromes?
Haeme proteins that transfer electrons in the electron transport chain ## Footnote Cytochromes play a crucial role in cellular respiration.
29
What is a key function of iron in enzymes?
Iron is a cofactor in hundreds of enzymes, including those involved in energy production and amino acid metabolism ## Footnote Iron-containing enzymes are essential for various metabolic processes.
30
How does excessive iron affect free radicals?
Excessive iron promotes the formation of highly reactive and destructive free radicals ## Footnote This highlights the importance of regulating iron levels in the body.
31
What role does iron play in energy metabolism?
Iron-containing enzymes are needed in the citric acid cycle and electron transport chain for ATP production ## Footnote ATP is the primary energy carrier in cells.
32
Fill in the blank: The change in oxidation state of iron allows for the transfer of _______.
electrons
33
What is the relationship between iron and muscle function?
Iron is involved in enzymes that support muscle function ## Footnote Adequate iron levels are crucial for physical performance and endurance.
34
What is one function of iron?
Immune function
35
What dilemma is associated with iron deficiency anemia?
Supplementation can worsen certain infections (e.g. malaria)
36
What does recent evidence suggest about iron supplementation in children?
It does not adversely affect children when regular malaria surveillance and treatment services are provided
37
True or False: Iron supplementation always worsens infections.
False
38
Fill in the blank: Iron deficiency anemia can lead to _______.
[supplementation dilemmas]
39
What organization provided evidence regarding iron supplementation and malaria?
WHO (World Health Organization), 2016
40
What is the role of iron in brain function?
Iron is essential for brain & nervous system development & function ## Footnote Iron plays a critical role in various neurological processes.
41
What protective covering does iron help produce in nerve cells?
Myelin sheath ## Footnote The myelin sheath is crucial for the proper functioning of nerve cells.
42
What type of chemical does iron help produce that carries messages between nerve cells?
Neurotransmitters ## Footnote Neurotransmitters are vital for communication within the nervous system.
43
What protein ferries iron through the blood?
Transferrin ## Footnote Transferrin is a glycoprotein that binds iron and transports it in the bloodstream.
44
Most iron in the body is stored as _______.
ferritin ## Footnote Ferritin is a protein complex that stores iron and releases it in a controlled manner.
45
Smaller amounts of iron are stored as _______.
hemosiderin ## Footnote Hemosiderin is an intracellular, insoluble form of iron storage that typically accumulates when there is excess iron in the body.
46
What is the primary function of transferrin?
To transport iron in the blood ## Footnote Transferrin plays a crucial role in iron metabolism and homeostasis.
47
True or False: Most of the body's iron is stored as hemosiderin.
False ## Footnote Most iron is stored as ferritin, with smaller amounts as hemosiderin.
48
How is iron transported in the blood?
As TRANSFERRIN ## Footnote Transferrin is a protein that binds to iron and transports it throughout the body.
49
What do transferrin receptors monitor?
Internal iron cell concentrations ## Footnote These receptors help regulate iron uptake by cells.
50
In what form is iron stored in the body?
As FERRITIN ## Footnote Ferritin is a protein complex that stores iron in a soluble and non-toxic form.
51
What does ferritin degrade into?
Haemosiderin ## Footnote Haemosiderin is an insoluble complex that stores excess iron.
52
Where is transferrin iron primarily absorbed?
In the liver cells (hepatocytes) ## Footnote Hepatocytes account for 60% of the body's iron.
53
What role does the spleen play in iron storage?
It contains reticulo-endothelial macrophages for iron stores ## Footnote These macrophages help recycle iron from old red blood cells.
54
What percentage of body iron is stored in circulating RBCs?
20% ## Footnote Red blood cells contain hemoglobin, which requires iron for oxygen transport.
55
What are the iron losses from the body?
80% ## Footnote This figure represents the total iron that is lost through various physiological processes.
56
What is the role of bone marrow in iron utilization?
It produces red blood cell precursors ## Footnote Bone marrow is essential for the formation of new red blood cells, which require iron.
57
What routine process releases iron in the body?
Routine destruction of old red blood cells ## Footnote This process is essential for maintaining iron levels.
58
What is recycled iron used for in the body?
To build new red blood cells ## Footnote Recycling iron is crucial for the continuous production of red blood cells.
59
When is dietary iron especially important?
In times of rapid growth and blood expansion ## Footnote Increased demand for iron occurs during periods such as childhood and pregnancy.
60
List the ways iron is lost from the body.
* Feces * Sweat * Skin cells * Menstruation ## Footnote These losses can contribute to iron deficiency if not compensated by dietary intake.
61
True or False: Digestive disorders can increase iron losses.
True ## Footnote Conditions affecting digestion can lead to higher rates of iron loss or reduced absorption.
62
What are the functional compounds of iron?
* Haemoglobin * Myoglobin * Haem enzymes * Nonhaem enzymes * Transferrin iron * Ferritin * Haemosiderin
63
What is the total iron content in males (mg/kg BW)?
37.05 mg/kg BW
64
What is the total iron content in females (mg/kg BW)?
33.05 mg/kg BW
65
Fill in the blank: The iron storage compound in the body is known as _______.
Ferritin
66
True or False: Myoglobin is a functional compound of iron.
True
67
What are the storage compounds of iron for males (mg/kg BW)?
* 9 * 4 * 13 * 50.05
68
What are the storage compounds of iron for females (mg/kg BW)?
* 4 * 1 * 5 * 38.05
69
What is the role of transferrin iron in the body?
Transferrin iron transports iron in the bloodstream
70
Fill in the blank: The compound that stores excess iron in the body is called _______.
Haemosiderin
71
How many mg/kg BW of iron do females have in haem enzymes?
1 mg/kg BW
72
How many mg/kg BW of iron do males have in nonhaem enzymes?
0.005 mg/kg BW
73
What are the inhibitors of iron absorption?
* Fiber and phytate * Calcium and phosphorus (milk/dairy) * Tannins, found in tea and coffee * Polyphenols * Oxalate ## Footnote Inhibitors can significantly reduce the bioavailability of iron from dietary sources.
74
What are the enhancers of iron absorption?
* Vitamin C (ascorbic acid) * Meat, poultry, and fish * Hydrochloric acid (HCI) secreted in the stomach * Citric, malic, and tartaric acids ## Footnote Enhancers improve the absorption of non-heme iron, making it more available for the body.
75
What is the first stage of iron deficiency?
Depletion of iron stores ## Footnote This stage is characterized by decreased ferritin levels.
76
What biochemical sign indicates depletion of functional iron?
Decreased transferrin saturation ## Footnote Transferrin saturation measures the residual binding capacity for iron.
77
What is a biochemical sign of iron-deficiency anemia?
Decreased hemoglobin ## Footnote Hemoglobin levels decrease significantly in iron-deficiency anemia.
78
What functional implication occurs during the depletion of functional iron?
Decreased physical performance ## Footnote This can lead to cognitive impairment and poor growth.
79
What occurs when there is an increased level of erythrocyte protoporphyrin?
Indicates a lack of iron saturation ## Footnote Increased protoporphyrin levels suggest that iron is not adequately available for hemoglobin synthesis.
80
What are the stages of iron deficiency listed?
* Depletion of iron stores * Depletion of functional iron * Iron-deficiency anemia ## Footnote These stages reflect the progression of iron deficiency and its impact on health.
81
What happens to red blood cell size in iron-deficiency anemia?
Decreased red blood cell size ## Footnote Smaller red blood cells are often observed in cases of iron deficiency.
82
Fill in the blank: Increased protoporphyrin levels indicate a lack of iron saturation, which means _______.
the body is unable to produce adequate hemoglobin.
83
True or False: There are no functional implications during the depletion of iron stores.
True ## Footnote Functional implications arise only in later stages of iron deficiency.
84
What is the most common nutrient deficiency?
Iron deficiency
85
What is the most severe stage of iron deficiency?
Iron-deficiency anemia
86
What does a lack of iron inhibit?
Red blood cell production
87
Name a symptom of iron-deficiency anemia.
Fatigue
88
Name another symptom of iron-deficiency anemia.
Pale skin
89
What is a deficiency that can lead to Anaemia?
Iron deficiency ## Footnote Iron deficiency is a common cause of anaemia.
90
What are the three stages of iron deficiency?
* Stage 1: Decreased storage iron (sFer) in liver, bone marrow, and spleen * Stage 2: Decreased circulating iron (sFe) in the blood * Stage 3: Decreased functional iron (Hb) ## Footnote These stages reflect the progression of iron deficiency leading to anaemia.
91
In which organ is storage iron (sFer) primarily found during Stage 1 of iron deficiency?
Liver ## Footnote Storage iron is also found in bone marrow and spleen.
92
What does Stage 2 of iron deficiency indicate?
Decreased circulating iron (sFe) in the blood ## Footnote This stage indicates that the iron available in the bloodstream is insufficient.
93
What is the primary indicator of functional iron deficiency in Stage 3?
Decreased functional iron (Hb) ## Footnote Hb refers to hemoglobin, which is crucial for oxygen transport in the blood.
94
True or False: Symptoms of iron deficiency are always apparent in Stage 1.
False ## Footnote Symptoms may not be evident until later stages of deficiency.
95
What are the two types of iron?
Haem iron and Non-haem iron
96
What is haem iron derived from?
Haemoglobin and myoglobin
97
Can haem iron be converted to non-haem iron?
Yes, it can be partially converted when cooked at high temperatures.
98
What is the main form of dietary iron?
Non-haem iron
99
What must happen to Fe before absorption takes place?
It needs to be released.
100
List some sources of haem iron.
* Meat * Fish * Poultry
101
List some sources of non-haem iron.
* Plant foods (nuts, cereals) * Dairy products
102
What is the best source of iron?
Lean red meat ## Footnote Lean red meat is considered the most effective source of iron for the body.
103
Name two other sources of iron besides lean red meat.
* Chicken * Turkey ## Footnote Chicken and turkey are good sources of iron, contributing to dietary needs.
104
Which food items are good sources of iron? List any three.
* Eggs * Cereals * Liver ## Footnote Eggs, cereals, and liver are additional sources that provide iron.
105
True or False: Oysters are a source of iron.
True ## Footnote Oysters are known to be rich in iron.
106
Fill in the blank: The dark meat of _______ is a source of iron.
[turkey] ## Footnote Dark meat from turkey contains higher iron levels compared to white meat.
107
What types of meat are considered good sources of iron? List any two.
* Beef * Clams ## Footnote Both beef and clams are excellent sources of iron.
108
What is the best source of iron?
Lean red meat ## Footnote Lean red meat is considered the most effective source of iron for the body.
109
Name two other sources of iron besides lean red meat.
* Chicken * Turkey ## Footnote Chicken and turkey are good sources of iron, contributing to dietary needs.
110
Which food items are good sources of iron? List any three.
* Eggs * Cereals * Liver ## Footnote Eggs, cereals, and liver are additional sources that provide iron.
111
True or False: Oysters are a source of iron.
True ## Footnote Oysters are known to be rich in iron.
112
Fill in the blank: The dark meat of _______ is a source of iron.
[turkey] ## Footnote Dark meat from turkey contains higher iron levels compared to white meat.
113
What types of meat are considered good sources of iron? List any two.
* Beef * Clams ## Footnote Both beef and clams are excellent sources of iron.
114
What are some sources of non-haem iron?
Fortified breakfast cereals, lentils, kidney beans, lima beans, pinto beans, molasses, tofu, spinach ## Footnote Non-haem iron is primarily found in plant-based foods and is not as easily absorbed as haem iron found in animal products.
115
Fill in the blank: _______ is a source of non-haem iron found in breakfast foods.
Fortified breakfast cereals
116
True or False: Spinach is a source of non-haem iron.
True
117
List three types of beans that are sources of non-haem iron.
* Kidney beans * Lima beans * Pinto beans
118
Which sweetener is listed as a source of non-haem iron?
Molasses
119
What plant-based protein is mentioned as a source of non-haem iron?
Tofu
120
What does bioavailability refer to?
The proportion of ingested mineral that is absorbed from the diet
121
True or False: Bioavailability can be enhanced or inhibited.
True
122
Fill in the blank: Bioavailability refers to the _______ of ingested mineral that is absorbed from the diet.
proportion
123
What factors can affect bioavailability?
Certain factors can enhance or inhibit bioavailability
124
What must happen to haem iron before absorption?
It must be separated from the globin portion of haemoglobin (or myoglobin) ## Footnote This process is essential for the absorption of haem iron in the body.
125
Which enzymes are responsible for separating haem iron from globin?
Proteases (stomach & Small Intestine) ## Footnote These enzymes break down proteins to facilitate the absorption of haem iron.
126
How is haem iron absorbed into the body?
It is easily absorbed into the mucosal cells ## Footnote The efficiency of this process is influenced by the body's iron status.
127
What does the absorption of haem iron depend on?
Iron status ## Footnote The body's current iron levels can significantly influence the absorption rate of haem iron.
128
What is the range of haem iron absorption in individuals with normal iron status?
15% ## Footnote This percentage indicates the efficiency of absorption when iron levels are adequate.
129
What is the maximum range of haem iron absorption in individuals who are iron deficient?
35% ## Footnote This increased absorption rate occurs when the body is in need of iron.
130
What is the chemical symbol for iron?
Fe
131
What type of iron needs to be liberated for absorption?
Non-haem iron
132
Which substances aid in liberating iron for absorption?
* Hydrochloric acid (HCl) * Proteases
133
What type of environment aids in the absorption of iron?
Acid environment
134
In which form is iron reduced for absorption?
Ferrous form Fe2+
135
What happens to iron when it passes into the small intestine?
It is oxidised to ferric iron Fe3+
136
What is the solubility of ferric iron (Fe3+)?
Insoluble
137
What is the typical absorption rate of iron?
1-10%
138
What are the factors inhibiting iron absorption?
Calcium, zinc, manganese, phytates, phenolic compounds, oxalic acid, EDTA ## Footnote Phytates are found in corn and whole grains; phenolic compounds are present in tea and coffee; oxalic acid is found in spinach, berries, and chocolate; EDTA is a common preservative.
139
What percentage of iron absorption does tea decrease?
60% ## Footnote Tea is a significant inhibitor of iron absorption due to its high phenolic compound content.
140
What percentage of iron absorption does coffee decrease?
10% ## Footnote Coffee, like tea, contains phenolic compounds that inhibit iron absorption.
141
Fill in the blank: _______ is a preservative that inhibits iron absorption.
EDTA
142
True or False: Oxalic acid can be found in chocolate.
True ## Footnote Oxalic acid is present in several foods, including chocolate, spinach, and berries.
143
What are the factors inhibiting iron absorption?
Calcium, zinc, manganese, phytates, phenolic compounds, oxalic acid, EDTA ## Footnote Phytates are found in corn and whole grains; phenolic compounds are present in tea and coffee; oxalic acid is found in spinach, berries, and chocolate; EDTA is a common preservative.
144
What percentage of iron absorption does tea decrease?
60% ## Footnote Tea is a significant inhibitor of iron absorption due to its high phenolic compound content.
145
What percentage of iron absorption does coffee decrease?
10% ## Footnote Coffee, like tea, contains phenolic compounds that inhibit iron absorption.
146
Fill in the blank: _______ is a preservative that inhibits iron absorption.
EDTA
147
True or False: Oxalic acid can be found in chocolate.
True ## Footnote Oxalic acid is present in several foods, including chocolate, spinach, and berries.
148
What compounds contain phytates and polyphenols?
Foods that bind zinc, calcium, and iron ## Footnote These compounds can interfere with the absorption of essential minerals.
149
Who is predisposed to deficiencies in certain minerals?
Vegetarians ## Footnote This is due to their dietary restrictions which may limit mineral intake.
150
What are the long-term effects of deficiencies in certain minerals?
* Osteoporosis * Anaemia ## Footnote These conditions can result from inadequate mineral intake over time.
151
What is the recommended daily intake of fiber according to SACN 2015?
30g/day ## Footnote This recommendation is based on dietary guidelines for maintaining health.
152
What are phenolic compounds?
Secreted by plants as defense mechanisms
153
Name a type of polyphenol containing food.
Tea (tannins)
154
List two other sources of polyphenol containing foods.
* Coffee * Cocoa
155
Which herbs and spices are known to contain phenolic compounds?
* Spinach * Oregano
156
What is advised regarding tea consumption during meals?
Avoid drinking tea with meals
157
What is an inhibitor of iron absorption?
Calcium ## Footnote One glass of milk can reduce iron absorption by 50%
158
What action possibly takes place in mucosal cells regarding iron absorption?
Calcium absorption inhibition ## Footnote This affects the bioavailability of iron in the diet.
159
What is a recommended solution to improve iron absorption when consuming calcium?
Separate consumption of Ca & Fe sources ## Footnote This helps minimize the interaction that inhibits iron absorption.
160
What is another recommended strategy to enhance iron intake?
Increase Fe intake ## Footnote This can help counteract the effects of calcium on iron absorption.
161
What is the main factor enhancing iron absorption?
Ascorbic acid ## Footnote Ascorbic acid, commonly known as Vitamin C, is known to enhance the absorption of iron.
162
Name three acids that enhance iron absorption.
* Citric acid * Lactic acid * Tartaric acid ## Footnote These acids are found in various fruits and can improve the bioavailability of iron.
163
What is another substance that enhances iron absorption?
Fructose ## Footnote Fructose is a simple sugar that can improve the absorption of iron.
164
Which sugar alcohol is known to enhance iron absorption?
Sorbitol ## Footnote Sorbitol is a sugar alcohol that may assist in iron absorption.
165
Does alcohol enhance iron absorption?
Yes ## Footnote Alcohol has been shown to enhance the absorption of iron in some studies.
166
What does ascorbic acid enhance?
Fe absorption, especially non-haem ## Footnote Ascorbic acid is known to increase the bioavailability of iron from plant sources.
167
How does ascorbic acid affect iron ions?
Reduces Fe3+ to Fe2+ ## Footnote This conversion makes iron more absorbable in the digestive tract.
168
What is the effect of 50mg of ascorbic acid on iron absorption?
Increases iron absorption significantly ## Footnote A specific dosage of ascorbic acid can dramatically enhance the body's ability to absorb iron.
169
What physiological factor increases heme iron absorption?
Low iron status ## Footnote Indicates a deficiency in iron levels in the body.
170
Name a dietary factor that increases non-heme iron absorption.
Ascorbic acid ## Footnote Commonly known as vitamin C, it enhances iron absorption.
171
What condition is associated with decreased iron absorption due to high iron status?
High heme iron intake ## Footnote Excessive intake of heme iron can inhibit further absorption.
172
List two physiological factors that can decrease iron absorption.
* High iron status * Achlorhydria (low gastric acid) ## Footnote Achlorhydria can hinder the absorption process of iron.
173
What disease states can affect iron absorption?
* Aplastic anemia * Hemolytic anemia * Hemochromatosis ## Footnote These conditions can alter the body's iron requirements and absorption capability.
174
Fill in the blank: _______ enhances the absorption of non-heme iron.
[Ascorbic acid]
175
What dietary factor can inhibit iron absorption?
Phytate ## Footnote Phytates are found in certain grains and legumes and can bind iron.
176
True or False: Low heme iron intake increases absorption of iron.
True ## Footnote Low intake of heme iron creates a physiological need for more absorption.
177
What role does calcium play in iron absorption?
Decreases absorption ## Footnote High calcium intake can compete with iron for absorption in the intestine.
178
What food sources are high in heme iron?
* Meat * Fish * Seafood ## Footnote Heme iron is primarily found in animal products.
179
What are the vital functions of Iron in the body?
Iron has several vital functions in the body.
180
How is iron absorption and metabolism regulated?
Absorption and metabolism are carefully regulated.
181
How does the absorption of haem and non-haem iron differ?
Haem iron is absorbed directly, while non-haem iron is hydrolysed.
182
What dietary factors can affect iron absorption?
Dietary factors can enhance or inhibit iron absorption.
183
What are the vital functions of Iron in the body?
Iron has several vital functions in the body.
184
How is iron absorption and metabolism regulated?
Absorption and metabolism are carefully regulated.
185
How does the absorption of haem and non-haem iron differ?
Haem iron is absorbed directly, while non-haem iron is hydrolysed.
186
What dietary factors can affect iron absorption?
Dietary factors can enhance or inhibit iron absorption.
187
What are the main components of the body?
All organs, tissues, fluids & secretions of the body ## Footnote This encompasses the entire biological structure and functions within a human or animal organism.
188
What is the second most abundant intracellular ion after iron?
Zinc ## Footnote Zinc plays a crucial role in various biological processes and is essential for human health.
189
Where is the highest concentration of zinc found in the body?
Hair, bone, liver, kidneys and muscles ## Footnote These tissues are critical for various metabolic functions and structural integrity.
190
Name other tissues with high zinc concentration.
* Cornea * Iris * Retina * Lens * Pancreas * Prostate * Spermatozoa * Skin * Finger and toe nails ## Footnote These tissues are involved in vision, reproduction, and protection, highlighting the importance of zinc in multiple physiological functions.
191
What is the role of Zn in plant and animal tissues?
Zn is involved in more than 200 enzymes including alcohol dehydrogenase, alkaline phosphatase, and RNA polymerase. ## Footnote These enzymes play critical roles in various metabolic processes.
192
List some metabolic processes Zn is involved in.
* Digestion * Carbohydrate metabolism * Bone metabolism * Oxygen transport * Antioxidant functions
193
True or False: Zn is important in the immune response.
True
194
What structural role does Zn play in proteins?
Zn provides structural properties in some proteins.
195
How does Zn stabilize genetic material?
Zn stabilizes the structure of DNA, RNA, and ribosomes.
196
What is the role of RNA polymerase in relation to Zn?
RNA polymerase is vital for the transcription of proteins.
197
Fill in the blank: Alkaline phosphatase plays a role in the synthesis of _______.
[proteins]
198
What organ systems does alkaline phosphatase primarily affect?
* Liver * Kidney * Bone
199
What is the role of alkaline phosphatase in bone?
Alkaline phosphatase is involved in bone mineralization.
200
What types of nucleic acids can alkaline phosphatase hydrolyze?
* DNA * RNA
201
What percentage of the body's zinc (Zn) is present in the blood?
<0.1% ## Footnote This indicates that blood measurement is not a reliable indicator of zinc status.
202
Why is the measurement of plasma zinc not a good measure of zinc status?
Because <0.1% of the body's Zn is present in the blood ## Footnote This low concentration makes plasma zinc measurements unreliable.
203
What increasingly used method measures thymulin activity?
Measurement of thymulin activity ## Footnote This method is labor-intensive and not widely available.
204
What role does thymulin play in the immune system?
Promotes T-lymphocyte maturation ## Footnote Thymulin requires zinc for its activity.
205
What is required for thymulin to be active?
Zinc ## Footnote Thymulin's activity is dependent on the presence of zinc.
206
What is the most reliable method of diagnosing zinc deficiency?
Zn supplementation and observation of the subject's response ## Footnote This method provides practical insight into zinc status.
207
What is the process by which zinc is released for absorption?
Zinc is hydrolysed from most amino acids & nucleic acids prior to absorption ## Footnote This process occurs during digestion, involving digestive enzymes.
208
Which enzymes are involved in the release of dietary zinc?
Proteases & nucleases ## Footnote These enzymes are found in the stomach and small intestine.
209
What can free zinc form coordination complexes with?
Different endogenous ligands including: * Amino acids * Phosphate * Other organic acids * Exogenous material in the intestinal lumen ## Footnote This occurs prior to transcellular uptake in the distal duodenum and proximal jejunum.
210
Which amino acids are preferred ligands for zinc due to their affinity for thiol and hydroxy groups?
Histidine and sulphur-containing amino acids: * Methionine * Cysteine ## Footnote These amino acids enhance the absorption of zinc.
211
Which zinc ligands are absorbed more efficiently in the lumen?
Zinc-histidine and zinc-methionine ## Footnote These ligands show better absorption rates compared to zinc-sulphate.
212
Fill in the blank: During digestion, digestive enzymes release dietary zinc from the food matrix as well as endogenous zinc from _______.
binding ligands
213
How is zinc absorbed most efficiently?
When cells have a zinc deficit ## Footnote This indicates that zinc absorption is enhanced when there is a deficiency in zinc levels within the cells.
214
What dietary component may inhibit zinc absorption?
Fiber ## Footnote High fiber diets can interfere with the absorption of zinc, potentially leading to lower levels in the body.
215
How does nonheme iron supplementation affect zinc absorption?
It can reduce zinc absorption ## Footnote Nonheme iron competes with zinc for absorption in the intestines.
216
What compound binds zinc and inhibits its absorption?
Phytate ## Footnote Phytate is found in various plant foods and can significantly reduce the bioavailability of zinc.
217
What happens to zinc content when intestinal cells are shed?
Their zinc content is excreted ## Footnote This process contributes to the regulation of zinc levels in the body.
218
What protein binds zinc in intestinal cells?
Metallothionein ## Footnote Metallothionein plays a crucial role in regulating the movement of zinc into the bloodstream.
219
How does zinc travel in the blood?
Bound to albumin or alpha-macroglobulin ## Footnote These proteins are essential for the transport of zinc throughout the body.
220
What are the two mechanisms of zinc uptake across the brush border surface?
Saturable carrier mediated mechanism & non-saturable passive mechanism ## Footnote The subcellular mechanisms of zinc uptake are not completely clear.
221
What is the main mechanism of zinc uptake at low to normal zinc intake?
Carrier mediated mechanism ## Footnote This mechanism does not require energy.
222
What happens to the capacity for carrier transporters at low dietary zinc intake?
The capacity for carrier transporters increases ## Footnote This may be due to a rise in the number of receptor sites.
223
What is the effect of low dietary zinc intake on carrier affinity?
The carrier affinity for zinc remains unchanged
224
What recent discoveries have improved the understanding of zinc uptake and homeostasis?
Zinc transporters (ZnT), zinc and iron-regulated proteins (ZIP), and metallothionein (MT) ## Footnote There are still unanswered questions about their roles.
225
What are the enhancers of zinc absorption?
* A protein rich diet (e.g. soy protein consumed alone or mixed with beef) * Physiologic situation (pregnancy and lactation, low zinc status) * Glucose and lactose * Picolinic acid and citric acid * Histidine, Cysteine and possibly other amino acids (lysine and glycine and methionine) * Glutathione * Vitamin D * Red wine (mentioned with no enhancing role) ## Footnote Lactose's enhancing role is not clearly defined, and some amino acids may not significantly enhance absorption.
226
What are the inhibitors of zinc absorption?
* Phytate, and phytate in presence of calcium * Divalent cations (e.g. calcium, iron, copper & cadmium) * Complexing agents (tannins, oxalate & polyphenols) * Dietary fibre (insoluble dietary fibre; major inhibitory role, soluble dietary fibre; minor or no inhibitory effect) * Intestinal diseases (e.g. Crohn disease) * Casein * Clay (important in geophagic cases) * Folic acid (reported with no inhibitory role) ## Footnote Some divalent cations and complexing agents have been reported with no significant inhibitory effects.
227
Fill in the blank: A _______ rich diet enhances zinc absorption.
[protein]
228
True or False: Lactose enhances zinc absorption.
False ## Footnote Lactose is mentioned but its role as an enhancer is not definitive.
229
Which physiological situations enhance zinc absorption?
* Pregnancy * Lactation * Low zinc status ## Footnote These conditions increase the body's demand for zinc.
230
Fill in the blank: _______ and _______ are amino acids that may enhance zinc absorption.
[Histidine], [Cysteine]
231
What role does dietary fibre play in zinc absorption?
* Insoluble dietary fibre has a major inhibitory role * Soluble dietary fibre has a minor or no inhibitory effect ## Footnote The type of dietary fibre affects zinc absorption differently.
232
Which intestinal disease is mentioned as an inhibitor of zinc absorption?
[Crohn disease]
233
What is the effect of clay on zinc absorption?
[Inhibitory, particularly in geophagic cases]
234
What is the main transporter of zinc in the bloodstream?
Albumin ## Footnote Albumin loosely binds to zinc to carry it from the intestinal cells to the liver.
235
How does zinc concentration in serum change with hypoalbuminemia?
Decreases ## Footnote Conditions like aging and protein energy malnutrition lead to decreased serum zinc concentration.
236
What percentage of plasma zinc is transported by albumin?
Up to 80% ## Footnote Albumin is responsible for the majority of plasma zinc transport.
237
What happens to zinc after it is transported to the liver?
It is released back into the bloodstream for delivery to other tissues.
238
Approximately how much zinc is usually circulating in the plasma?
About 3 mg
239
Fill in the blank: Albumin is _______ bound to zinc to carry it to the liver.
loosely
240
True or False: Zinc is only transported by albumin in the bloodstream.
False ## Footnote Other proteins like transferrin also transport zinc.
241
What factors can affect zinc concentration in the serum?
Aging, protein energy malnutrition, hypoalbuminemia ## Footnote These conditions can lead to altered zinc levels in the bloodstream.
242
Which protein is responsible for transporting the remaining bound zinc not carried by albumin?
Transferrin
243
What does the pancreas secrete as part of digestive enzymes?
Copious amounts of zinc ## Footnote Zinc is essential for various physiological functions, including digestion.
244
Which proteins carry zinc in the blood?
Albumin and alpha-macroglobulin ## Footnote These proteins play a crucial role in transporting zinc to various tissues.
245
How is zinc lost from the body?
Via urine, skin, semen, and lost blood ## Footnote These pathways highlight the need for regular dietary intake of zinc.
246
What percentage of the body's zinc is contained in muscle and bone?
90% ## Footnote Muscle and bone are major reservoirs for zinc in the body.
247
What role do intestinal cells play in zinc management?
Absorb and recycle most of the zinc in digestive enzymes ## Footnote This process helps maintain zinc homeostasis within the body.
248
Fill in the blank: The pancreas secretes copious amounts of _______ as part of digestive enzymes.
zinc
249
True or False: Most of the body's zinc is found in the liver.
False ## Footnote Most of the body's zinc is actually found in muscle and bone.
250
Which two amino acids have a loose bond to zinc in blood?
Histidine and cysteine ## Footnote These amino acids are suggested to be associated with 2-8% of zinc transport.
251
What determines the amount of zinc filtered by the kidneys?
The amino acid bind fraction ## Footnote This fraction is influenced by histidine and cysteine.
252
Which tissues have slow uptake of zinc and retain it for a long time?
Central nervous system and bone ## Footnote Zinc in these tissues stays strongly bound and is not usually available for metabolic use.
253
Is bone zinc usually available for metabolic use?
No ## Footnote Bone zinc is not usually available for metabolic use.
254
What happens to hair zinc when hair is shed?
It is lost to the tissues ## Footnote Hair zinc is not available to the tissues.
255
Which organs have the quickest rates of zinc accumulation and turnover?
Pancreas, liver, kidney, and spleen ## Footnote These organs process zinc more rapidly than others.
256
Which cells exhibit relatively slower zinc uptake and turnover?
Red blood cells and muscles ## Footnote These tissues have slower rates of zinc accumulation.
257
What is the relationship between tissue zinc concentration and plasma zinc concentration?
Minor variations in tissue zinc concentration can have a major impact on plasma zinc concentration. ## Footnote For instance, a 1% increase in liver zinc concentration could cause a 40% decrease in plasma zinc.
258
What happens to part of the released zinc in the body?
Part of the released zinc can go back into the enterocytes and to the intestinal lumen. ## Footnote This process is part of the zinc turnover and transport within the body.
259
What role does albumin-bound zinc in plasma play?
It appears to have a role in the regulation of zinc absorption. ## Footnote Albumin-bound zinc is the fraction ready to be taken up by tissues.
260
What are the two phases suggested for the entry of zinc into cells?
* Saturable rapid uptake (likely carrier mediated) * Slower passive uptake ## Footnote Understanding these phases is important for comprehending zinc uptake mechanisms.
261
True or False: The total amount of zinc in plasma is greater than that in major tissues.
False ## Footnote The total amount of zinc in plasma is much smaller than the total amount present in major tissues.
262
What is the major route of zinc excretion?
Faeces ## Footnote Studies show that only 2-10% of zinc is recovered in urine, the rest is excreted via faeces.
263
What are the sources of zinc in faeces?
Unabsorbed dietary zinc & endogenous zinc secretions ## Footnote Endogenous zinc secretions mainly come from pancreatic secretions.
264
What increases pancreatic secretion of zinc after eating?
Eating a meal ## Footnote Much of the zinc secreted into the gut is absorbed and returned to the body.
265
What role does zinc enteropancreatic circulation play?
Zinc homeostasis ## Footnote It helps maintain zinc levels in the body.
266
What is the usual daily urinary zinc excretion range?
300-600 µg ## Footnote This is minor compared to faecal zinc losses.
267
What dietary conditions can impact urinary zinc losses?
Extremely low and extremely high dietary zinc intake ## Footnote These conditions can alter the usual minor urinary zinc excretion.
268
What percentage of filtered zinc is usually reabsorbed in the distal renal tubule?
Up to 95% ## Footnote This indicates efficient reabsorption of zinc by the body.
269
What factors can cause a dramatic rise in urinary zinc excretions?
Muscle catabolism, severe burns, major surgery, trauma, starvation ## Footnote These conditions increase the metabolic demand for zinc.
270
What are the other sources of body zinc excretion?
Surface losses, semen, menstrual secretions ## Footnote Skin, hair, and sweat also contribute to zinc loss.
271
What is Zinc?
Zinc is found in all plant and animal tissues.
272
Which food sources are particularly high in Zinc?
* Meat * Cereal products * Liver * Beef * Chicken * Pork * Peanut butter * Oysters
273
What is the approximate amount of Zinc contained in an adult human?
Approx. 2g ## Footnote Zinc is an essential trace mineral necessary for various biological functions.
274
In which tissues is Zinc primarily found?
Skeletal muscle, bone, and skin ## Footnote These are the main depots for Zinc in the body.
275
Why are Zinc depots in the body not a reliable source during deprivation?
Zinc turnover from these tissues is slow ## Footnote This slow turnover means that the body cannot quickly access stored Zinc in times of need.
276
What is the absorption rate of Zinc from food?
Approx. 20-40% ## Footnote This variable absorption rate can depend on dietary factors.
277
What is the Recommended Nutrient Intake (RNI) of Zinc for males?
9.5mg/d ## Footnote This value represents the daily intake recommended for adult males.
278
What is the Recommended Nutrient Intake (RNI) of Zinc for females?
7.0mg/d ## Footnote This value represents the daily intake recommended for adult females.
279
What is a common symptom of zinc deficiency?
Depressed appetite ## Footnote Zinc deficiency can lead to various symptoms, including changes in appetite.
280
What is a potential effect of zinc deficiency on taste?
Poor taste acuity ## Footnote Zinc plays a critical role in taste perception.
281
What is one of the effects of zinc deficiency on wound healing?
Delayed wound healing ## Footnote Zinc is essential for proper immune function and wound repair.
282
How does zinc deficiency affect growth?
Poor growth ## Footnote Zinc is important for growth and development.
283
What developmental issue can zinc deficiency cause in children?
Delayed sexual maturation in children ## Footnote Adequate zinc levels are crucial for normal sexual development.
284
What is a consequence of zinc deficiency related to the immune system?
Immuno-suppression ## Footnote Zinc is vital for maintaining a healthy immune response.
285
What condition can be caused by a metabolic defect related to zinc?
Acrodermatitis enteropathica ## Footnote This condition is characterized by severe zinc deficiency due to impaired absorption.
286
What are the symptoms of Acrodermatitis enteropathica?
* Severe rash * Growth failure * Behavioural abnormalities ## Footnote These symptoms arise from a metabolic defect affecting zinc uptake.
287
What is one of the key functions of zinc in the body?
Intestinal uptake of zinc ## Footnote Proper zinc absorption is crucial for various bodily functions.
288
True or False: Zinc deficiency can lead to skeletal abnormalities.
True ## Footnote Zinc is important for bone health and development.
289
What are some deficiency signs of trace minerals?
* Poor prenatal development * Growth retardation * Mental retardation * Impaired nerve conduction & nerve damage * Reproductive failure * Dermatitis * Hair loss ## Footnote These signs indicate potential health issues related to insufficient trace minerals in the diet.
290
What are two deficiency signs of trace minerals?
Diarrhoea, Loss of appetite ## Footnote Additional deficiency signs include loss of taste and smell, anaemia, susceptibility to infections, delayed wound healing, and macular degeneration.
291
Which trace minerals are mentioned?
Zinc, Copper ## Footnote These minerals are essential for various bodily functions.
292
Fill in the blank: A deficiency in trace minerals can lead to _______.
diarrhoea
293
True or False: Delayed wound healing is a sign of trace mineral deficiency.
True
294
List three signs of trace mineral deficiency.
* Loss of appetite * Loss of taste and smell * Anaemia
295
What condition related to vision can result from trace mineral deficiency?
Macular degeneration
296
Fill in the blank: Susceptibility to infections can be a sign of _______.
trace mineral deficiency
297
What is a common symptom of trace mineral deficiency that affects the digestive system?
Diarrhoea
298
Name one effect of trace mineral deficiency on the immune system.
Increased susceptibility to infections
299
Fill in the blank: A loss of _______ can indicate a deficiency in trace minerals.
taste and smell
300
What is dietary zinc toxicity?
Dietary zinc toxicity is rare ## Footnote Refers to adverse effects from excessive zinc intake.
301
List four symptoms of acute zinc toxicity.
* Abdominal pain * Nausea and vomiting * Lethargy * Anaemia * Dizziness ## Footnote These symptoms can arise from high levels of zinc consumption.
302
True or False: Dietary zinc toxicity is common.
False ## Footnote Dietary zinc toxicity is considered rare.
303
What is a potential cause of zinc toxicity?
Ingestion of water stored in galvanized tanks or use for renal dialysis ## Footnote Zinc can leach from galvanized surfaces into the water.
304
What symptoms can acute ingestion of 2 grams or more of zinc cause?
Nausea, vomiting, and fever
305
What intake level of zinc has been shown to interfere with copper and iron metabolism?
50 mg
306
What are the chronic intake levels of zinc associated with symptoms of copper deficiency?
75-300 mg/d
307
What symptoms are associated with copper deficiency due to chronic zinc intake?
* Microcytic anemia * Neutropenia
308
What are the effects of zinc excess on the brain?
Lethargy and focal neuronal deficits ## Footnote Zinc excess can lead to various neurological issues including lethargy and specific deficits in neuronal function.
309
What respiratory disorder can occur due to inhalation of zinc smoke?
Metal fume fever ## Footnote Metal fume fever is a condition associated with inhaling metal oxides, often resulting from welding or metalworking.
310
List gastrointestinal symptoms associated with zinc excess.
* Nausea/vomiting * Epigastric pain * Diarrhea ## Footnote These symptoms can occur due to irritation of the gastrointestinal tract from excess zinc.
311
What is the elevated risk associated with zinc excess in the prostate?
Elevated risk of prostate cancer ## Footnote Research suggests a correlation between zinc excess and an increased risk of developing prostate cancer.
312
How does zinc excess affect nerve conduction?
Decreased nerve conduction ## Footnote Excess zinc can impair the transmission of nerve signals, leading to decreased conduction velocities.
313
Identify neuropsychiatric disorders related to zinc excess.
Neuropsychiatric disorders and neurosensory disorders ## Footnote Zinc excess can lead to a variety of mental health issues and sensory processing problems.
314
What are the effects of zinc excess on the thymus?
Thymic atrophy ## Footnote Zinc excess can negatively affect immune function by causing atrophy of the thymus gland.
315
List skin-related effects of zinc excess.
* Skin lesions * Decreased wound healing * Acrodermatitis ## Footnote These skin conditions can arise due to excess zinc impacting skin health and healing processes.
316
What reproductive issues can arise from zinc excess?
* Infertility * Retarded genital development * Hypogonadism ## Footnote Excessive zinc levels can disrupt normal reproductive functions and development.
317
What systemic symptoms can arise from copper deficiency?
* Growth retardation * Immune dysfunction and infection ## Footnote Copper deficiency can lead to significant systemic health issues, including impaired growth and weakened immune response.
318
What is the effect of copper deficiency on lymphocyte function?
Altered lymphocyte function ## Footnote Copper is essential for proper immune function, and its deficiency can compromise lymphocyte activity.
319
What is the total amount of copper (Cu) in an adult's body?
80 mg ## Footnote This is the total copper content in a typical adult.
320
What percentage of copper in the body is found in muscle?
40% ## Footnote Muscle tissue contains the highest percentage of copper.
321
What percentage of copper is located in the liver?
15% ## Footnote The liver plays a significant role in copper storage.
322
What percentage of copper is found in the brain?
10% ## Footnote Copper is essential for brain health and function.
323
What percentage of copper is present in blood?
6% ## Footnote Copper is also transported in the bloodstream.
324
Where else is copper distributed in the body aside from muscle, liver, brain, and blood?
Heart, bone, hair, and nails ## Footnote These tissues also contain smaller amounts of copper.
325
What are high food sources of zinc?
Nuts, Shellfish, Offal, Cereal and cereal products, Meat and meat products ## Footnote High concentrations of zinc are found in nuts (8 mg/kg), shellfish (40 mg/kg), and offal (40 mg/day)
326
What is the concentration of zinc in shellfish?
40 mg/kg ## Footnote Shellfish is one of the richest sources of zinc.
327
What is the concentration of zinc found in nuts?
8 mg/kg ## Footnote Nuts are a significant source of zinc but contain lower concentrations compared to shellfish.
328
What is the daily zinc intake from offal?
40 mg/day ## Footnote Offal is a high source of zinc that provides a substantial amount of daily intake.
329
Fill in the blank: High concentrations of zinc are found in _______.
Nuts, Shellfish, Offal, Cereal and cereal products, Meat and meat products
330
What are the functions of several enzymes that require trace minerals?
They are involved in various biochemical processes including host defence mechanisms, red and white cell maturation, iron transport, cholesterol and glucose metabolism, myocardial contractibility, and brain development & function. ## Footnote Trace minerals like zinc and copper play critical roles in enzyme function.
331
What is a key role of trace minerals in infant growth?
Trace minerals are required for infant growth. ## Footnote Adequate trace mineral intake is crucial for proper development during infancy.
332
Fill in the blank: Trace minerals are involved in _______ mechanisms.
host defence ## Footnote This includes immune responses and protection against pathogens.
333
True or False: Trace minerals have no impact on cholesterol and glucose metabolism.
False ## Footnote Trace minerals play a significant role in the metabolism of cholesterol and glucose.
334
What is one of the roles of trace minerals in red and white cell maturation?
They are essential for the maturation process of these cells. ## Footnote This is crucial for the body's ability to transport oxygen and fight infections.
335
Fill in the blank: Trace minerals contribute to _______ transport.
iron ## Footnote Iron transport is vital for oxygen delivery in the body.
336
What role do trace minerals play in myocardial contractibility?
They are involved in the contractibility of the heart muscle. ## Footnote This is essential for effective heart function and circulation.
337
How do trace minerals affect brain development?
They are important for brain development & function. ## Footnote Adequate levels of trace minerals are necessary for cognitive functions.
338
What is the function of Cytochrome-C Oxidase?
Reduction of O2 to H2O ## Footnote It is part of the electron transport chain in cellular respiration.
339
What role does Caeroplasmin (ferrooxidase I) play?
Iron oxidation and transport ## Footnote It helps in the transportation of iron in the bloodstream.
340
What is the function of Superoxide dismutase?
Antioxidant ## Footnote It protects cells from oxidative damage by dismutating superoxide radicals.
341
What does Dopamin hydroxylase do?
Hydroxylation of dopa in the brain ## Footnote This enzyme is crucial for the synthesis of neurotransmitters.
342
What is the function of Lysyl Oxidase?
Cross-linking in collagen and elastin ## Footnote This process is important for maintaining the structural integrity of connective tissues.
343
What is the role of Chaperone proteins?
Intracellular Cu transport ## Footnote They assist in the proper folding and transport of proteins within cells.
344
What is the function of Clotting factors V and VII?
Thrombogenesis ## Footnote These factors are essential for the blood coagulation process.
345
What does Metallothionein do?
Metal sequestration ## Footnote It binds heavy metals and helps in detoxification.
346
What is the function of Nitrous oxide reductase?
Reduction of NO2 to NO ## Footnote This enzyme is involved in the nitrogen cycle and helps in reducing nitrogen oxides.
347
What is a reliable method of assessing Cu status?
A totally reliable, sensitive method has yet to be established ## Footnote Current assessments often rely on plasma Cu and caeruloplasmin.
348
What is caeruloplasmin?
A Cu-containing protein that normally binds 90% of the Cu present in plasma ## Footnote It is frequently used to assess copper status.
349
How do plasma Cu and caeruloplasmin respond in deficiency?
Both are lowered in deficiency ## Footnote However, they plateau as levels of Cu increase.
350
What is the normal serum Cu level range?
12-26 pg/I ## Footnote Levels can be affected by late pregnancy and estrogen-based contraceptive use.
351
What happens to serum Cu levels during late pregnancy?
They are frequently elevated ## Footnote This can affect the assessment of copper status.
352
What other method can be used to assess Cu status?
Assessment of the activity of Cu enzymes, particularly superoxide dismutase ## Footnote This method may provide additional insights into copper status.
353
What is a rare condition that can occur in premature infants and patients receiving total parenteral nutrition?
Copper deficiency ## Footnote Copper deficiency is uncommon but can occur under specific conditions.
354
When is copper accumulated in the fetus?
During the late stages of pregnancy ## Footnote Full-term babies have large stores of copper.
355
In which diseases can copper losses occur?
* Cystic fibrosis * Coeliac disease * Chronic diarrhoea in children ## Footnote These conditions can lead to a deficiency in copper due to malabsorption or other metabolic issues.
356
What hereditary condition is associated with impaired copper transport?
Menkes disease ## Footnote Menkes disease leads to significant copper deficiency due to the inability to transport copper effectively.
357
Fill in the blank: Cu deficiency is rare although it can occur in _______ and in patients receiving total parenteral nutrition.
premature infants
358
What is a symptom of copper deficiency in babies?
Failure to thrive in babies ## Footnote This indicates inadequate growth or development.
359
What condition is associated with low serum albumin in copper deficiency?
Oedema ## Footnote Oedema refers to swelling caused by excess fluid trapped in the body's tissues.
360
What type of anemia is resistant to iron in the context of copper deficiency?
Fe resistant anaemia ## Footnote This type of anemia does not improve with iron supplementation.
361
What is a consequence of impaired immunity due to copper deficiency?
Low neutrophil count ## Footnote Neutrophils are a type of white blood cell important for fighting infections.
362
What skeletal changes can occur due to copper deficiency?
Fractures and osteoporosis ## Footnote Osteoporosis is a condition characterized by weak and brittle bones.
363
What type of blood vessel defect is associated with copper deficiency?
Abnormal blood vessels due to defects in collagen and elastin ## Footnote Collagen and elastin are crucial for maintaining the structural integrity of blood vessels.
364
What are the effects of copper deficiency on hair and skin?
Hypopigmentation with steely, uncrimped hair ## Footnote Hypopigmentation refers to a decrease in normal skin color.
365
What neurological issues can arise from copper deficiency?
Neurological abnormalities ## Footnote These can include problems with coordination, balance, and other cognitive functions.
366
True or False: Copper deficiency may increase the risk of coronary heart disease.
True ## Footnote It has been associated with raised plasma cholesterol levels and heart-related abnormalities.
367
What is Cu toxicity caused by?
Deliberate ingestion of Cu salts or drinking contaminated water ## Footnote Cu toxicity can manifest in both acute and chronic forms.
368
What are the symptoms of acute Cu toxicity?
Nausea, vomiting, and diarrhoea; may be fatal in extreme cases ## Footnote Acute symptoms can occur rapidly following exposure.
369
What can chronic Cu poisoning lead to?
Liver cirrhosis ## Footnote Infants and young children are particularly vulnerable to chronic Cu poisoning.
370
What is Wilson's disease?
An inherited disease characterized by abnormal Cu transport resulting in Cu accumulation in the liver, eyes, brain, and kidneys ## Footnote Wilson's disease leads to various associated pathologies.
371
Who is particularly vulnerable to chronic Cu poisoning?
Infants and young children ## Footnote Their developing systems make them more susceptible to the effects of copper.
372
What are dietary sources of Iodine?
* Marine fish * Shellfish * Edible seaweed * Meat * Eggs * Iodised salt ## Footnote Amounts in different foods vary, especially vegetables where levels depend on the amount in soil.
373
True or False: Iodine levels in vegetables are consistent regardless of soil quality.
False ## Footnote Iodine levels in vegetables depend on the amount of iodine present in the soil.
374
What are dietary sources of Iodine?
* Marine fish * Shellfish * Edible seaweed * Meat * Eggs * Iodised salt ## Footnote Amounts in different foods vary, especially vegetables where levels depend on the amount in soil.
375
True or False: Iodine levels in vegetables are consistent regardless of soil quality.
False ## Footnote Iodine levels in vegetables depend on the amount of iodine present in the soil.
376
What is the RNI for adults for iodine?
140 micrograms/day
377
What are the mean iodine intakes in the UK?
159-215 micrograms/day
378
What food source contributes the highest iodine intake in the UK?
Milk
379
Fill in the blank: The RNI for iodine is _______.
140 micrograms/day
380
True or False: The highest iodine intake in the UK comes from milk due to iodine used in cattle feed.
True
381
What factors contribute to the iodine content in milk?
Iodine used in cattle feed and disinfectants used in cattle sheds
382
What form does iodine exist in the body?
Iodide (I*) ## Footnote Iodide is less toxic compared to iodine.
383
How is iodine ingested in food processed in the body?
Converted to iodide in the gut ## Footnote This conversion allows for safer absorption into the body.
384
What carries iodide into the circulation?
Serum proteins ## Footnote These proteins play a crucial role in transporting iodide throughout the body.
385
What is the main function of iodine?
Synthesis of the hormone thyroxine (T4) and Tri-iodiothyronine (T3) ## Footnote Iodine is critical for the production of thyroid hormones which are essential for metabolism.
386
What role does iodine play in fetal development?
Normal development of the foetal nervous system ## Footnote Adequate iodine levels are crucial during pregnancy to support brain development in the fetus.
387
What is one component of healthy connective tissue that iodine contributes to?
Component of healthy connective tissue ## Footnote Iodine is involved in maintaining the structural integrity of connective tissues.
388
How does iodine protect against radioactivity?
Protection against effects of radioactivity ## Footnote Iodine can help prevent the absorption of radioactive isotopes in the thyroid gland.
389
What effect does iodine have on estrogen regulation in breast tissue?
Regulate the effects of estrogen on breast tissue ## Footnote Iodine may influence estrogen activity, potentially impacting breast health.
390
What controls the secretion of thyroid hormones?
Thyroid-stimulating hormone (TSH) produced by the pituitary gland ## Footnote TSH regulates the activity of the thyroid gland and thus the production of thyroid hormones.
391
List the functions of thyroid hormones.
* Regulation of body temperature * Control of metabolic rate * Cellular metabolism * Integrity of cell membranes * Reproduction and growth ## Footnote These functions are crucial for maintaining overall body homeostasis.
392
True or False: Thyroid hormones are responsible for the regulation of body temperature.
True ## Footnote Thyroid hormones play a significant role in thermoregulation.
393
Fill in the blank: The secretion of thyroid hormones is controlled by _______.
Thyroid-stimulating hormone (TSH) ## Footnote TSH is essential for the proper functioning of the thyroid gland.
394
What gland produces thyroid-stimulating hormone (TSH)?
Pituitary gland ## Footnote The pituitary gland is often referred to as the 'master gland' because it controls various hormonal functions.
395
What condition is indicated by an under-active thyroid gland?
Hypothyroidism ## Footnote Hypothyroidism occurs when the thyroid gland does not produce enough thyroid hormones.
396
What are common symptoms of hypothyroidism?
* Fatigue * Weight gain * Cold intolerance * Depression * Dry skin * Hair loss * Constipation * Muscle weakness ## Footnote Symptoms can vary among individuals.
397
True or False: An under-active thyroid gland can lead to weight loss.
False ## Footnote An under-active thyroid typically causes weight gain rather than loss.
398
Fill in the blank: An under-active thyroid gland does not produce enough _______.
thyroid hormones ## Footnote Thyroid hormones are crucial for regulating metabolism and energy levels.
399
What symptom might indicate a deficiency in thyroid hormones?
Fatigue ## Footnote Fatigue is a common symptom associated with low levels of thyroid hormones.
400
What is the primary disorder caused by iodine deficiency?
Goitre ## Footnote Goitre is an enlargement of the thyroid gland due to insufficient iodine.
401
What are the two types of cretinism associated with iodine deficiency?
* Neurological cretinism * Hypothyroid cretinism ## Footnote These types refer to the different manifestations of severe iodine deficiency during development.
402
What condition is characterized by underactivity of the thyroid gland?
Hypothyroidism ## Footnote Hypothyroidism can lead to various health issues, including fatigue and weight gain.
403
What are the potential effects of neurological cretinism?
* Neurological disability * Mental retardation ## Footnote Neurological cretinism can lead to severe cognitive impairments.
404
Fill in the blank: Iodine deficiency can lead to _______.
Goitre ## Footnote Goitre is a visible symptom of iodine deficiency.
405
True or False: Hypothyroid cretinism leads to neurological disabilities.
False ## Footnote Hypothyroid cretinism primarily results in thyroid-related issues rather than neurological disabilities.
406
What is a common care method for managing hypothyroidism?
Iodine supplementation ## Footnote Iodine supplementation can help prevent and treat conditions related to iodine deficiency.
407
What causes a Goitre?
When the blood iodine level is low, cells of the thyroid gland enlarge. ## Footnote Goitre becomes visible when the enlargement of the thyroid gland is significant.
408
What is the visible enlargement of the thyroid gland called?
Goitre. ## Footnote A Goitre can block the trachea and may require removal.
409
Does a Goitre affect health?
It does not affect health until it blocks the trachea. ## Footnote Removal of the Goitre may be necessary if it obstructs breathing.
410
What are the two types of Cretinism?
Neurological cretinism and myxedematous cretinism ## Footnote Neurological cretinism is due to iodine deficiency during pregnancy, while myxedematous cretinism is related to iodine deficiency occurring after birth.
411
What causes neurological cretinism?
Iodine deficiency occurring very early on in pregnancy ## Footnote This condition is irreversible after conception.
412
List some symptoms of neurological cretinism.
* Low IQ * Deafness * Mutism * Spastic diplegia * Affected linear growth ## Footnote These symptoms highlight the severe impact of iodine deficiency on development.
413
Define Mutism.
Inability to speak ## Footnote This condition is one of the symptoms associated with neurological cretinism.
414
What is the overall impact of Cretinism?
Severely stunted physical and mental growth ## Footnote Cretinism can have lifelong effects on an individual's development.
415
What is hypothyroid cretinism?
A condition resulting from maternal iodine deficiency late in pregnancy.
416
What are the symptoms of cretinism?
* Failure to gain weight * Sleepiness * Thick dry skin * Hoarse cry * Slow mental development
417
When can signs of cretinism improve or disappear?
If iodine is given early, before 12 months of age.
418
What is hypothyroid cretinism?
A condition resulting from maternal iodine deficiency late in pregnancy.
419
What are the symptoms of cretinism?
* Failure to gain weight * Sleepiness * Thick dry skin * Hoarse cry * Slow mental development
420
When can signs of cretinism improve or disappear?
If iodine is given early, before 12 months of age.
421
What is hypothyroidism?
A condition where the thyroid gland fails to produce enough hormones ## Footnote It is more common in women over 50 years of age.
422
What is a common cause of hypothyroidism?
Autoimmune disease (Hashimoto's thyroiditis) ## Footnote Hashimoto's thyroiditis is an autoimmune disorder where the immune system attacks the thyroid gland.
423
What is a treatment for hyperthyroidism that can lead to hypothyroidism?
Too much reduction treatment ## Footnote This refers to treatments that excessively lower thyroid hormone levels.
424
What type of therapy can lead to hypothyroidism?
Radiation therapy (Head and Neck) ## Footnote Radiation therapy can damage the thyroid gland, leading to decreased hormone production.
425
What are the causes of hypothyroidism?
Hypothyroidism can be caused by: * Thyroid surgery * Medications (e.g. Lithium) * Congenital disease * Pituitary disorder * Pregnancy * Iodine deficiency ## Footnote These causes highlight various factors that can lead to decreased thyroid hormone production.
426
What is primary hypothyroidism?
Thyroid can't produce the amount of hormones needed ## Footnote In primary hypothyroidism, the thyroid gland itself is dysfunctional.
427
What is secondary hypothyroidism?
Thyroid isn't being stimulated by the pituitary to produce hormones ## Footnote In secondary hypothyroidism, the issue lies with the pituitary gland not signaling the thyroid.
428
What are common symptoms of hypothyroidism?
* Increased sensitivity to cold * Constipation * Pale, dry skin * A puffy face * Hoarse voice * Elevated cholesterol level ## Footnote These symptoms indicate an underactive thyroid gland, which can affect metabolism and overall health.
429
What is a symptom of hypothyroidism related to weight?
Unexplained weight gain ## Footnote This symptom indicates an imbalance in metabolism due to reduced thyroid hormone levels.
430
List three symptoms of hypothyroidism.
* Muscle aches, tenderness and stiffness * Pain, stiffness and swelling in joints * Muscle weakness
431
What menstrual symptom may indicate hypothyroidism?
Heavier than normal menstrual periods ## Footnote Changes in menstrual cycles can be a sign of hormonal imbalances.
432
Which mental health condition can be a symptom of hypothyroidism?
Depression ## Footnote Depression can arise due to the effects of low thyroid hormone levels on mood regulation.
433
Fill in the blank: A common symptom of hypothyroidism is _______.
muscle weakness
434
True or False: Joint pain is a symptom of hypothyroidism.
True
435
What type of muscle discomfort may be experienced in hypothyroidism?
Muscle aches, tenderness and stiffness ## Footnote These symptoms can significantly affect daily activities and quality of life.
436
What is a symptom of hypothyroidism related to weight?
Unexplained weight gain ## Footnote This symptom indicates an imbalance in metabolism due to reduced thyroid hormone levels.
437
List three symptoms of hypothyroidism.
* Muscle aches, tenderness and stiffness * Pain, stiffness and swelling in joints * Muscle weakness
438
What menstrual symptom may indicate hypothyroidism?
Heavier than normal menstrual periods ## Footnote Changes in menstrual cycles can be a sign of hormonal imbalances.
439
Which mental health condition can be a symptom of hypothyroidism?
Depression ## Footnote Depression can arise due to the effects of low thyroid hormone levels on mood regulation.
440
Fill in the blank: A common symptom of hypothyroidism is _______.
muscle weakness
441
True or False: Joint pain is a symptom of hypothyroidism.
True
442
What type of muscle discomfort may be experienced in hypothyroidism?
Muscle aches, tenderness and stiffness ## Footnote These symptoms can significantly affect daily activities and quality of life.
443
What is myxedema?
A dry, waxy type of swelling (non-pitting oedema) with abnormal deposits of mucin in the skin and other tissues, associated with hypothyroidism. ## Footnote The facial changes are distinctive, with swollen lips and thickened nose.
444
What condition is myxedema associated with?
Hypothyroidism. ## Footnote Myxedema can be rare and life-threatening.
445
List the signs and symptoms of myxedema.
* Low blood pressure * Decreased breathing * Decreased body temperature * Unresponsiveness * Coma ## Footnote These symptoms indicate severe hypothyroidism.
446
True or False: Myxedema can be life threatening.
True. ## Footnote It is important to recognize and treat myxedema promptly.
447
What type of edema is associated with myxedema?
Non-pitting oedema. ## Footnote This type of swelling does not retain indentations when pressed.
448
What is myxedema?
A dry, waxy type of swelling (non-pitting oedema) with abnormal deposits of mucin in the skin and other tissues, associated with hypothyroidism. ## Footnote The facial changes are distinctive, with swollen lips and thickened nose.
449
What condition is myxedema associated with?
Hypothyroidism. ## Footnote Myxedema can be rare and life-threatening.
450
List the signs and symptoms of myxedema.
* Low blood pressure * Decreased breathing * Decreased body temperature * Unresponsiveness * Coma ## Footnote These symptoms indicate severe hypothyroidism.
451
True or False: Myxedema can be life threatening.
True. ## Footnote It is important to recognize and treat myxedema promptly.
452
What type of edema is associated with myxedema?
Non-pitting oedema. ## Footnote This type of swelling does not retain indentations when pressed.
453
What are common symptoms of hypothyroidism in newborns?
Jaundice, frequent choking, large protruding tongue, trouble feeding, fail to grow and develop normally, constipation, poor muscle tone, excessive sleepiness, severe physical and mental retardation ## Footnote Symptoms may vary in severity and can significantly impact the newborn's health and development.
454
Fill in the blank: A large __________ is a symptom of hypothyroidism in newborns.
protruding tongue
455
True or False: Excessive sleepiness is a symptom of hypothyroidism in newborns.
True
456
What is one of the developmental issues associated with hypothyroidism in newborns?
Fail to grow and develop normally ## Footnote This can lead to long-term health issues if not addressed.
457
List three symptoms of hypothyroidism in newborns.
* Jaundice * Frequent choking * Poor muscle tone
458
Fill in the blank: Constipation is a symptom of __________ in newborns.
hypothyroidism
459
What is a severe consequence of untreated hypothyroidism in newborns?
Severe physical and mental retardation
460
What are some signs and symptoms of trace mineral deficiencies in teens?
Similar signs and symptoms to adults but also: * Poor growth resulting in short stature * Hypothyroidism * Delayed development of permanent teeth * Delayed puberty * Poor mental development ## Footnote Trace minerals are essential for various bodily functions, and their deficiency can lead to significant developmental issues in adolescents.
461
What are goitrogens?
Substances that reduce the amount of iodine that the thyroid gland can absorb from the blood.
462
Do goitrogens cause iodine deficiency?
No, they do not cause iodine deficiency; rather, they make it worse.
463
Name examples of foods containing goitrogens.
* Bamboo shoots * Cassava * Broccoli * Kale * Lima beans * Peanuts * Sweet potato * Tea
464
How can most goitrogens present in food be inactivated?
By cooking.
465
Which minerals can act as goitrogenic agents?
* Calcium * Magnesium * Manganese * Fluoride ## Footnote Goitrogenic agents interfere with thyroid function by affecting iodine utilization.
466
What role does competition for receptors play in mineral interactions?
Competition for receptors may be a factor. ## Footnote This suggests that certain minerals may inhibit or alter the effects of others by competing for the same binding sites.
467
What level of iodine intake is generally tolerated by most people?
Most people are tolerant to a wide range of iodine intakes
468
What is the maximum intake of iodine per day that shows no adverse effects?
No adverse effects are seen up to 2mg iodine/day
469
Under what circumstances are toxic levels of iodine more likely to occur?
Toxic levels unlikely to be achieved in the normal diet - more likely to occur due to contamination of food or water
470
What condition can occur in the thyroid gland due to excessive iodine consumption?
Thyroid gland can enlarge - has been seen in those who have consumed large quantities of seaweed
471
What sensitivity might some individuals have related to iodine intake?
Iodine sensitivity seen in some and may result in skin irritations if higher than normal intakes
472
What is selenium linked to in food?
Protein content as seleno amino acids: selenomethionine or selenocysteine ## Footnote Selenomethionine and selenocysteine are the two primary forms of selenium found in proteins.
473
Which animal foods are the richest sources of selenium?
Meat, fish, and eggs ## Footnote These foods typically have higher selenium levels due to the diet of the animals.
474
Name a food that is considered a very high source of selenium.
Brazil nuts ## Footnote Brazil nuts are known to have one of the highest concentrations of selenium among foods.
475
What type of cereals are considered moderate sources of selenium?
Wholegrain cereals ## Footnote The selenium content in wholegrain cereals can vary depending on the soil in which they are grown.
476
What factors influence the selenium content in fruits and vegetables?
Soil content ## Footnote The amount of selenium in fruits and vegetables is greatly influenced by the selenium levels in the soil they are grown in.
477
What is the selenium content in soil in Europe?
Low
478
What is the selenium content in soil in North America?
Rich
479
What is the selenium status in rural China?
Deficient
480
What is the selenium content in soil in Europe?
Low
481
What is the selenium content in soil in North America?
Rich
482
What is the selenium status in rural China?
Deficient
483
What has caused selenium intakes to fall in the UK?
The decline in import of North American selenium-rich wheat and increased use of European cereals which are less rich in selenium. ## Footnote According to BNF (2009), some bread manufacturers still import wheat from North America.
484
Which type of wheat is rich in selenium?
North American wheat. ## Footnote This is contrasted with European cereals, which are less rich in the mineral.
485
Fill in the blank: Some bread manufacturers still import wheat from _______.
North America.
486
True or False: The use of European cereals has contributed to an increase in selenium intake in the UK.
False.
487
What mineral's intake has declined in the UK due to changes in wheat imports?
Selenium.
488
What percentage of dietary selenium is absorbed?
55-65% ## Footnote Absorption rates indicate the efficiency of selenium uptake from dietary sources.
489
Where is most selenium found in the body?
Liver, kidneys, muscle, red blood cells, and plasma ## Footnote These organs and tissues play crucial roles in selenium metabolism and function.
490
How are selenium levels regulated in the body?
Through the kidneys ## Footnote The kidneys help maintain homeostasis of selenium by filtering and excreting excess amounts.
491
What is the Recommended Nutrient Intake (RNI) of selenium for healthy adult men?
75 µg/day ## Footnote This value reflects dietary guidelines to ensure adequate selenium intake for men.
492
What is the Recommended Nutrient Intake (RNI) of selenium for healthy adult women?
60 µg/day ## Footnote This value reflects dietary guidelines to ensure adequate selenium intake for women.
493
What is the estimated UK intake of selenium per day?
40 µg/day ## Footnote This figure indicates the average selenium consumption in the UK and suggests a potential decline in intake.
494
True or False: The UK intake of selenium is thought to be increasing.
False ## Footnote The text suggests that selenium intake in the UK is believed to be falling.
495
What is the role of selenium in the body?
Required in enzymes production ## Footnote Selenium is crucial for the formation of proteins and is involved in various metabolic processes.
496
Name an antioxidant enzyme that selenium is a component of.
Glutathione peroxidase ## Footnote This enzyme protects cells from oxidative damage.
497
What is the function of thioredoxin reductase?
Required in DNA synthesis ## Footnote This enzyme plays a vital role in maintaining the redox state of the cell.
498
Fill in the blank: Selenium is involved in _______ metabolism.
Iodine ## Footnote Proper iodine metabolism is essential for thyroid function.
499
What is the range of proteins that selenium helps form in the body?
12-30 proteins ## Footnote These proteins are essential for various biological functions.
500
What can adequate vitamin E partly compensate for?
Lack of selenium
501
Is clinical deficiency of selenium usually seen in the UK?
No, except in unnatural conditions i.e. IV feed
502
What health issues have low dietary intakes of selenium been linked to?
* CHD * Cancer * Decreased immune function
503
What disease leads to cardiomyopathy and is associated with selenium deficiency?
Keshan disease
504
Which populations are primarily affected by Keshan disease?
* Children * Women of child bearing age in China
505
What severe health issue can gross deficiency of selenium lead to?
Osteoarthrisis
506
What is the name of the disease associated with osteoarthrisis due to selenium deficiency?
Kashin-Beck disease
507
What can adequate vitamin E partly compensate for?
Lack of selenium
508
Is clinical deficiency of selenium usually seen in the UK?
No, except in unnatural conditions i.e. IV feed
509
What health issues have low dietary intakes of selenium been linked to?
* CHD * Cancer * Decreased immune function
510
What disease leads to cardiomyopathy and is associated with selenium deficiency?
Keshan disease
511
Which populations are primarily affected by Keshan disease?
* Children * Women of child bearing age in China
512
What severe health issue can gross deficiency of selenium lead to?
Osteoarthrisis
513
What is the name of the disease associated with osteoarthrisis due to selenium deficiency?
Kashin-Beck disease
514
What is the toxicity of selenium?
Exceedingly toxic in excess amounts ## Footnote Selenium is an essential trace element, but in high doses, it can lead to toxicity.
515
List three symptoms of selenium excess.
* Brittle hair and nails * Skin lesions * Garlic odour on breath ## Footnote These symptoms indicate selenium toxicity and should be taken seriously.
516
What are the health benefits of selenium?
Selenium has various health benefits including: * Anti-cancer * Anti-asthma * Anti-arthritis * Anti-muscular dystrophy * Anti-cystic fibrosis ## Footnote These benefits are mainly due to the antioxidant effects of selenoenzymes.
517
How does selenium improve fertility?
Selenium is vital in sperm cell development and function and reduces the risk of miscarriage. ## Footnote Selenium's role in fertility is linked to its antioxidant properties.
518
What is the impact of selenium deficiency on viral infections?
Under selenium-deficient conditions, RNA viruses such as influenza, HIV, hepatitis B and C, and measles multiply faster, and disease progresses faster. ## Footnote Selenium deficiency can lead to a weakened immune response against these viruses.
519
What are selenoenzymes and their roles?
Over 35 selenoenzymes have vital roles including: * Thyroid hormone regulation * Antioxidant effects * DNA synthesis ## Footnote Selenoenzymes are crucial for maintaining various physiological functions.
520
How does selenium contribute to anti-aging?
Selenium preserves DNA integrity and maintains telomere length, inhibiting the aging process. ## Footnote It also reduces mitochondrial oxidative stress.
521
What effect does selenium have on immunity?
Selenium boosts immunity by stimulating: * Neutrophils * NK cells * B cells * T cells * Macrophages ## Footnote This stimulation enhances the body's ability to fight infections.
522
How does selenium improve brain function?
Selenium protects brain cells and alleviates depression, anxiety, and cognitive decline. ## Footnote Its antioxidant properties may play a role in these protective effects.
523
What are the cardiovascular benefits of selenium?
Selenium reduces: * Inflammation * Cholesterol plaque buildup * Lipid peroxidation * Homocysteine levels * Regulates blood pressure ## Footnote These factors contribute to a lower risk of heart disease.
524
What is the amount of manganese in the human body?
10-20 mg ## Footnote Manganese is an essential trace mineral.
525
What percentage of manganese is found in the bone?
25% ## Footnote Manganese plays a role in bone formation and maintenance.
526
Is manganese deficiency common?
No, it is very rare ## Footnote Adequate intake of manganese is usually achieved through diet.
527
What percentage of dietary Manganese is typically absorbed in the small intestine?
Around 10% ## Footnote Some studies have reported absorption as low as 3%
528
What factors impair the absorption of Manganese?
High intakes of Ca, P, and phytate ## Footnote These factors can significantly reduce how much Manganese is absorbed
529
What happens to Manganese absorption rates when intakes are low?
Absorption rate increases and there is renal conservation ## Footnote This means the body retains more Manganese when dietary intake is insufficient
530
What percentage of dietary Manganese is typically absorbed in the small intestine?
Around 10% ## Footnote Some studies have reported absorption rates as low as 3%
531
What factors impair the absorption of Manganese?
High intakes of Ca, P and phytate ## Footnote These factors can hinder the body's ability to absorb Manganese effectively.
532
What happens to the absorption rate of Manganese if intakes are low?
The absorption rate increases and there is renal conservation ## Footnote This indicates the body's adaptive mechanisms to conserve essential minerals when intake is insufficient.
533
What percentage of dietary Manganese is typically absorbed in the small intestine?
Around 10% ## Footnote Some studies have reported absorption rates as low as 3%
534
What factors impair the absorption of Manganese?
High intakes of Ca, P and phytate ## Footnote These factors can hinder the body's ability to absorb Manganese effectively.
535
What happens to the absorption rate of Manganese if intakes are low?
The absorption rate increases and there is renal conservation ## Footnote This indicates the body's adaptive mechanisms to conserve essential minerals when intake is insufficient.
536
What is the typical dietary intake of trace minerals for most adults?
2-3 mg/day (up to 8 mg/d) ## Footnote This range indicates the general consumption levels for trace minerals.
537
Name three main sources of trace minerals.
* Cereal and cereal products * Vegetables * Tea * Fruits * Nuts ## Footnote Nuts are particularly noted for having high levels of trace minerals.
538
Which type of diet is particularly abundant in trace minerals?
Plant-based diets ## Footnote Plant-based diets often provide higher levels of trace minerals compared to animal-based diets.
539
What is a key constituent of metalloenzymes?
Manganese ## Footnote Manganese acts as an enzyme activator.
540
What classes of enzymes have manganese cofactors?
Lyases, ligases, transferases ## Footnote These classes of enzymes are very broad.
541
What potential role does manganese have in the body?
Maintaining spinal bone density ## Footnote Manganese may contribute to bone health.
542
What is a main feature induced by experimental diets?
Reduction in blood lipids including cholesterol ## Footnote Other signs may include weight loss, growth retardation, and skin rash.
543
What can low intakes of manganese very early in pregnancy contribute to?
Foetal abnormalities ## Footnote This highlights the importance of adequate manganese intake during early pregnancy.
544
What conditions have been found in children with low blood and/or hair concentrations of manganese?
Skeletal abnormalities, osteoporosis, and epilepsy ## Footnote These conditions indicate the critical role of manganese in child development.
545
Under normal conditions, is dietary toxicity of manganese likely?
No, dietary toxicity is unlikely under normal conditions.
546
What parkinsonian syndrome has been documented in Greece?
An increased incidence of a parkinsonian syndrome due to high manganese concentration in the water.
547
What are the psychological effects of excess inhalation of manganese?
'Manganic madness' - psychosis, hallucinations, and features of Parkinson's disease.
548
What effect does excess manganese have on iron absorption?
Excess manganese can inhibit iron absorption.
549
What is the absorption rate of fluoride from food sources?
50-80% absorbed from food sources
550
What substance may inhibit the absorption of fluoride?
Calcium
551
Where is fluoride mainly taken up in the body?
Bones and teeth
552
What is the crystal structure that fluoride is incorporated into?
Fluoroapatite
553
How does fluoroapatite compare to apatite in terms of hardness?
Fluoroapatite is harder than apatite
554
Which organ controls body levels of fluoride?
Kidneys
555
What is fluoride bound to in the blood?
Albumin
556
Approximately what percentage of fluoride intake is excreted in urine?
Approx. 50%
557
What is apatite?
A group of phosphate minerals
558
What are the primary sources of trace minerals?
Tap water, tea, sea foods, vegetables ## Footnote The trace mineral content of vegetables depends on soil levels.
559
What is the average daily intake of trace minerals for adults?
0.2-2.8 mg/day depending on water levels
560
What role does fluoride play in bone mineralisation?
Fluoride accelerates the remineralisation process, especially when oral pH falls due to the action of bacteria on sugar. ## Footnote Fluoride is crucial for maintaining dental health and preventing decay.
561
How does fluoride affect the hardness of enamel on teeth?
Fluoride makes enamel on teeth harder and more resistant to caries. ## Footnote This contributes to overall dental health and reduced cavity formation.
562
What is the association between low intakes of fluoride and dental health?
Low intakes of fluoride are associated with a higher incidence of dental caries. ## Footnote This indicates that adequate fluoride intake is important for preventing tooth decay.
563
What effect does the addition of fluoride to water have on dental caries?
The addition of 1 mg/kg fluoride to water reduces caries with reported reductions of 50%. ## Footnote This public health measure is aimed at improving community dental health.
564
Can fluoride stimulate new bone formation?
Yes, fluoride can stimulate new bone formation and is being used as an experimental drug in osteoporosis. ## Footnote Research is ongoing to evaluate its effectiveness and safety in treating bone-related conditions.
565
What intake level in children greater than _______ mg/kg causes mottling of the teeth?
0.1 mg/kg ## Footnote This condition is referred to as mild fluorosis.
566
Adding fluoride to drinking water is considered a _______ issue.
controversial ## Footnote While 1 mg/I may be beneficial, higher levels can be toxic.
567
What is the term for fluoride toxicity?
Fluorosis ## Footnote Fluorosis can present in mild and severe forms.
568
What are the symptoms of mild fluorosis?
mottling of teeth ## Footnote This is a cosmetic defect caused by excessive fluoride.
569
What are the symptoms of severe fluorosis?
calcification of ligaments, spinal defects ## Footnote Severe fluorosis can lead to significant physical issues.
570
High incidence of fluorosis is noted in which regions?
* South Africa * China * Indian subcontinent ## Footnote These areas have high fluoride concentrations in the soil that contaminate water supplies.
571
What is the toxic level of fluoride mentioned in the text?
10 g/I ## Footnote This level is considered toxic, while 1 mg/I is seen as beneficial.
572
What mineral is associated with links to various diseases?
Fluoride ## Footnote Fluoride has been reported in media concerning its association with bone cancer and arthritis.
573
Which systems can fluoride affect?
Fluoride can affect the: * kidneys * brain * nervous system * immune system ## Footnote The impact of fluoride on these systems is a concern in health discussions.
574
True or False: Current evidence on fluoride's health effects is extensive.
False ## Footnote At present, evidence regarding the health effects of fluoride is limited.
575
In what forms does Chromium exist?
Trivalent and hexavalent forms
576
What is the absorption rate of chromium from inorganic sources?
0.5-2%
577
What is the absorption rate of chromium from organic sources?
10-25%
578
How is chromium transported in the body?
By transferrin and plasma proteins
579
How is chromium mainly excreted from the body?
In the urine
580
What are good sources of Chromium?
Meat (esp. beef), whole grains, legumes, nuts, brewer's yeast ## Footnote Refined foods are low in Chromium.
581
Fill in the blank: Refined foods are low in _______.
Chromium
582
What are the reported deficiency symptoms for trace minerals?
Deficiency symptoms reported on intakes of 6ug/d ## Footnote Limited study data has resulted in no RNI's being set.
583
What is believed to be the safe and adequate level of trace minerals intake?
Believed to lie above 25pg/d ## Footnote This level is based on current understanding and studies.
584
What is the range of adult intake of trace minerals according to studies?
About 13-49pg/d ## Footnote This range provides insight into typical consumption patterns.
585
True or False: RNI's have been set for trace minerals.
False ## Footnote RNI's have not been established due to limited study data.
586
Fill in the blank: The safe and adequate level of trace minerals is believed to be above _______.
25pg/d
587
What is the lowest reported intake for trace minerals that shows deficiency symptoms?
6ug/d
588
What are the deficiency symptoms reported on intakes of?
6ug/d ## Footnote Deficiency symptoms can indicate the importance of adequate nutrient levels.
589
Why are RNI's not set for certain nutrients?
Due to limited study data ## Footnote RNI stands for Reference Nutrient Intake.
590
What is the believed safe and adequate level of intake?
Above 25ug/d ## Footnote This level is considered to prevent deficiency symptoms.
591
What is the range of adults' intake of the nutrient studied?
13-49pg/d ## Footnote This indicates variability in dietary intake among adults.
592
What are the deficiency symptoms reported on intakes of?
6ug/d ## Footnote Deficiency symptoms can indicate the importance of adequate nutrient levels.
593
Why are RNI's not set for certain nutrients?
Due to limited study data ## Footnote RNI stands for Reference Nutrient Intake.
594
What is the believed safe and adequate level of intake?
Above 25ug/d ## Footnote This level is considered to prevent deficiency symptoms.
595
What is the range of adults' intake of the nutrient studied?
13-49pg/d ## Footnote This indicates variability in dietary intake among adults.
596
What is the effect of Chromium on insulin?
Insulin is more effective in the presence of Chromium
597
What impact do Chromium supplements have on HDL cholesterol?
Chromium supplements have been shown to increase HDL cholesterol
598
What role might Chromium play in RNA synthesis?
RNA synthesis from DNA may require Chromium
599
How does Chromium affect insulin receptors?
Chromium may optimise the number of membrane insulin receptors or their interaction with insulin or both
600
What is the effect of Chromium on insulin?
Insulin is more effective in the presence of Chromium
601
What impact do Chromium supplements have on HDL cholesterol?
Chromium supplements have been shown to increase HDL cholesterol
602
What role might Chromium play in RNA synthesis?
RNA synthesis from DNA may require Chromium
603
How does Chromium affect insulin receptors?
Chromium may optimise the number of membrane insulin receptors or their interaction with insulin or both
604
What are the deficiency signs described in adults and children on prolonged parenteral feeding?
Insulin-resistant hyperglycaemia, elevated serum lipids, ataxia, peripheral neuropathy, encephalopathy ## Footnote These signs indicate a potential deficiency in trace minerals.
605
True or False: Deficiency signs are described only in adults.
False ## Footnote Deficiency signs are also noted in children on prolonged parenteral feeding.
606
Fill in the blank: Signs of deficiency include _______.
insulin-resistant hyperglycaemia, elevated serum lipids, ataxia, peripheral neuropathy, encephalopathy
607
What is a possible neurological sign of deficiency in trace minerals?
Encephalopathy ## Footnote This condition reflects significant neurological impact due to trace mineral deficiency.
608
List some metabolic signs associated with deficiency.
* Insulin-resistant hyperglycaemia * Elevated serum lipids
609
What condition can manifest as ataxia in the context of trace mineral deficiency?
Neurological impairment ## Footnote Ataxia is a lack of voluntary coordination of muscle movements.
610
What are the deficiency signs described in adults and children on prolonged parenteral feeding?
Insulin-resistant hyperglycaemia, elevated serum lipids, ataxia, peripheral neuropathy, encephalopathy ## Footnote These signs indicate a potential deficiency in trace minerals.
611
True or False: Deficiency signs are described only in adults.
False ## Footnote Deficiency signs are also noted in children on prolonged parenteral feeding.
612
Fill in the blank: Signs of deficiency include _______.
insulin-resistant hyperglycaemia, elevated serum lipids, ataxia, peripheral neuropathy, encephalopathy
613
What is a possible neurological sign of deficiency in trace minerals?
Encephalopathy ## Footnote This condition reflects significant neurological impact due to trace mineral deficiency.
614
List some metabolic signs associated with deficiency.
* Insulin-resistant hyperglycaemia * Elevated serum lipids
615
What condition can manifest as ataxia in the context of trace mineral deficiency?
Neurological impairment ## Footnote Ataxia is a lack of voluntary coordination of muscle movements.
616
What are dietary sources of molybdenum?
Vegetables grown on neutral or alkaline soils, especially ground plants such as legumes and cauliflower. ## Footnote Molybdenum can be found in various plants, particularly those that thrive in specific soil conditions.
617
What effect can plants grown in Mo-rich soils have?
They may give rise to toxic effects. ## Footnote Excessive molybdenum in soil can lead to harmful concentrations in plants.
618
What nutrients does molybdenum interact with in the diet?
Copper and sulphates. ## Footnote These interactions can influence the absorption of molybdenum.
619
True or False: Molybdenum is only present in animal sources.
False. ## Footnote Molybdenum is predominantly found in plant sources.
620
Fill in the blank: Molybdenum interacts with _______ and sulphates present in the diet.
copper ## Footnote The presence of these elements can affect nutrient absorption.
621
What type of soil is associated with higher molybdenum content in plants?
Neutral or alkaline soils. ## Footnote Soil pH plays a crucial role in nutrient availability.
622
What is the absorption rate for trace minerals?
25-93% absorption
623
Which form of molybdenum is more readily absorbed?
Soluble molybdenum
624
How does renal excretion relate to trace minerals?
Renal excretion is affected by absorption rate
625
What is a co-factor for major enzymes in human tissue?
Trace minerals ## Footnote Trace minerals are essential for various biochemical reactions in the body.
626
Which enzymes are required for the metabolism of purines?
Enzymes that metabolize purines, pyrimidines, quinolines, sulphite, and bisulphite ## Footnote These enzymes are crucial for nucleic acid metabolism and detoxification processes.
627
Fill in the blank: Trace minerals act as _______ for major enzymes in human tissue.
co-factors
628
What is a co-factor for major enzymes in human tissue?
Trace minerals ## Footnote Trace minerals are essential for various biochemical reactions in the body.
629
Which enzymes are required for the metabolism of purines?
Enzymes that metabolize purines, pyrimidines, quinolines, sulphite, and bisulphite ## Footnote These enzymes are crucial for nucleic acid metabolism and detoxification processes.
630
Fill in the blank: Trace minerals act as _______ for major enzymes in human tissue.
co-factors
631
What is the estimated requirement of molybdenum?
0.1-0.3 mg/day
632
Is molybdenum deficiency commonly found?
Not normally found
633
What is an inborn error of metabolism related to molybdenum?
Defect in the synthesis of molybdenum co-factor
634
What are the symptoms of an inborn error of metabolism related to molybdenum?
* Severe development retardation * Neurological abnormalities * Impaired metabolism of sulphur amino acids and nucleotides

Nutrition (24 decks)

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