Chapter 10-Micronutrients Flashcards
1
Q
what are the two types of micronutrients
A
organic vitamins
inorganic minerals
2
Q
which two vitamins play a role in body tissues ?
A
vit C and D
3
Q
which three minerals play a role in body tissues ?
A
Ca, P, F
4
Q
which vitamin group is a cofactor for enzymes ?
A
vit B
5
Q
which two minerals are cofactors for enzymes ?
A
Zinc, Mg
6
Q
which mineral is crucial for oxygen transport ?
A
iron
7
Q
which two vitamins are important for oxidative metabolism ?
A
niacin, riboflavin
8
Q
which 3 vitamins are antioxidants ?
A
vit C, vit E, beta carotene
9
Q
which two minerals are antioxidants
A
copper-manganese as part of SOD (superoxide dismutase)
and selenium as part of GSSH (gluthatione)
10
Q
what are 4 methods to assess nutritional status ?
A
ABCD anthropometrics- waist circumference, weight biochemical- blood tests clinical- physical exam dietary- 24 hr recall
11
Q
what is the advantage of biochemical tests ?
A
usually detect nutrient discrepancies before altered anthropometrics and clinical signs and symptoms
12
Q
are physical signs of deficiency reliable ?
A
not really, always do blood tests
13
Q
blood work is not relevant for which mineral
A
Calcium
14
Q
what is a disadvantage of blood work ?
A
some signs are non-specific
15
Q
what are two examples of non-specific signs ?
A
swollen corners of the lips
angular stomatitis/ angular cheilitis
16
Q
what can angular stomatitis/ angular cheilitis be caused by? which deficiencies (4)
A
vitamin B
PEM (protein)
iron
zinc
17
Q
what is the normal color of the tongue ?
A
light red
18
Q
what is glossitis ?
A
smoothening of the tongue where it is usually covered with taste buds
19
Q
glossitis can be a sign of which deficiencies (6 vit, 2 minerals, 1 other thing)
A
riboflavin niacin biotin vit B6 vit B12 folate
iron,zinc
drug-nutrient interactions
20
Q
pallor in tongue is a sign of which deficiency (3 vit, 2 minerals)
A
folate, biotin, vit B12
copper, iron
21
Q
what is inadequate intake
A
low variety, low cal, very low fat
22
Q
what disorders cause nutrient deficiencies
A
crohn’s, celiac
23
Q
what condition alters metabolism to the point where there might be a nutrient deficiency
A
alcoholism
24
Q
is there true evidence that consuming micronutrients in excess of RDA improves performance ?
A
no
25
which three vitamins can in part be produced by the body ?
```
vitamin D (sunlight)
K and selected B which can be produced by the bacterial microflora
```
26
how do vitamins directly contribute to energy supply ?
they do not !
27
which vitamin deficiency causes premature fatigue and inability to maintain a heavy training program ?
B
28
which two vitamins are crucial for maintaining healthy populations of cells (eg RBC)
folic acid and B12 (because they are involved in nucleic acid synthesis)
29
which vitamin is important for blood clotting ?
K (glycoproteins)
30
what are 5 rolels of micronutrients ?
```
structural
enzyme and cofactors in metabolism of macros
antioxidants and immune function
electrolytes and acid-base balance
nerve transmission, muscle contraction
```
31
is more vitamins better ? what is the proof ?
no, since we have an Upper Limit for many nutrients
32
what is vitamin intake correlated with? what does it mean ?
it is correlated with energy intake, meaning that you shouldn't become deficient with energy intake equal to estimated requirements
33
does physical activity increase requirement of vitamins ? what are the implications ?
yes for some: C, riboflavin, and maybe others. but can be met by consuming a high carb, moderate protein, low fat diet.
34
how does one compensate vitamin losses in sweat, urine, and feces ?
you don't need to, the losses are negligible.
35
how does exercise affect vitamin turnover ?
it doesn't
36
physical activity may increase the requirements of which B vitamins? why?
(B2) riboflavin and B6
| due to increased retention of those in skeletal muscle mitochondria for energy metabolism
37
physical activity may increase the requirements of which class of vitamins ?
antioxidants, due to increased free radical production during exercise
38
what are the three free radicals produced by oxidation in the mitochondria ?
superoxide, hydroxyl, nitric oxide
39
are vitamins organic or inorganic
organic
40
are minerals organic or inorganic
inorganic
41
what element do minerals not contain
C
42
what 4+ elements do vitamins contain
C, H, O, N
and metal ions (copper, iron, sulfur, cobalt)
43
how many identified vitamins ?
13
44
how many minerals are essential for humans ?
20
45
how are vitamins classified ?
by solubility
46
how are minerals classified ?
macro and micro minerals
47
do vitamins and minerals take part in body mass ?
vitamins, no
| minerals, yes
48
are vitamins structural ?
no
49
which three minerals are structural ?
calcium, phosphorus, fluorine
50
what is the only water soluble vitamin stored ?
B12
51
which type of vitamin is mostly required from the diet ?
water soluble
52
what are the three sources for fat soluble vitamins ?
diet, gut bacteria (K), sun (D)
53
what are the 7 macrominerals ?
CCMPPSS
```
Chloride
Calcium
Magnesium
Phosphorus
Potassium
Sodium
Sulfur
```
54
what is the abbrev for 7 macrominerals ?
CCMPPSS
55
which 3 minerals are used for enzymes ?
magnesium, copper, zinc
56
which two minerals are crucial for immune cells ?
iron and zinc
57
why is it that vitamin needs of physically active people generally do not exceed those of sedentary people ?
because vitamins are recycled in body
58
what are the 3 causes of fat-soluble vitamin deficiencies ?
malabsorption : surgical or medical causes (like intestinal resection, or lack of fat digestive enzymes in pancreas)
GI or hepatic disorders
low cal diet (<700kcal /day)
59
what are the main 3 roles in the body of vit A ?
maintain epithelial tissues in skin, pigments of eye
bone development
immune function
60
what is the scientific word for vit A ?
retinol
61
what are three consequences of vit A deficiency ?
night blindness, infections, impaired growth
62
what are effects of excess vit A ?
nausea, joint pains, peeling skin, abnormal fetal development
63
what is the word for the primary form of vit D ?
calcitriol
64
what are two deficiency diseases of vit D ?
rickets in kids
| osteomalacia in adults
65
what is a consequence of vit D toxicity?
hypercalcemia meaining calcification of tissues eg kidneys, arrhythmias, depressed CNS, constipation (as well as nausea, loss of appetite, etc)
66
what is the word for vit E ?
alpha-tocopherol
67
what is the main role of vit E
antioxidant
68
what is the main consequence of vit E deficiency? what are three consequences ?
cell membrane damage
meaning muscle weakness, hemolytic anemia, loss of motor coordination
69
what is the main role of vit K ?
forms glycoprotein blood clotting factors
70
what happens w a vit K deficiency?
hemorrhage
71
what is a consequence of vit K excess ?
thrombosis
72
what is the main consequence (medical) of a vit A deficiency?
keratinization of skin, meaning immature skin cells (keratinocytes) do not mature and can't secret mucus, so they secrete keratin and become hard.
this can cause hyperkeratosis, blindness, etc
73
what are our two sources of vit D ?
diet and sun
74
explain how sunlight becomes calcitriol in vit D
D3 (cholecalciferol) goes to liver, becomes CALCIDIOL
| liver CALCIDIOL becomes kidney CALCITRIOL with the help of parathyroid hormone
75
how does diet vit D become calcitriol ?
D3 and D2 go into chylomicrons to liver, become CALCIDIOL, converted to CALCITRIOL in kidneys
76
what are the three areas of the body with vit D calcitriol receptors ?
intestines, bones, other tissues
77
what does calcitriol do to the intestine ?
increases absorption of calcium and phosphorus
78
what does calcitriol do to bone
assists parathyroid hormone in stimulating osteoclasts to break down bone and release calcium into blood
79
how does calcitriol affect tissues other than bone and intestine ?
aid cell differentiation and inhibit cell proliferation
80
can you get vit D excess from sun ?
no
81
what population has a vit D deficiency ? for what three reasons
North Americans above 30degN latitude
sun not strong enough in winter, in summer cover up due to cancer risk
older adults
dark skinned individuals
82
how much sun required per day to avoid vit D deficiency?
5-30 min
83
where is vit E stored ?
adipose tissue and cell membranes ?
84
what are the different forms of vit E ?
8 forms with varying biological activity
| only 1 form (alpha tocopherol) needed in humans
85
what dose would cause an excess of vit E?
>400 IU/d
86
use of what medication could contribute to a vit K deficiency ?
antibiotics
87
what does vit K do precisely on a structural level
adds sugars to proteins
88
which fat-soluble vitamin has an RDA, not an AI? what is it ?
vit D
| has an RDA of 15 micrograms/d for both males and females
89
what are the main two roles of water soluble vitamins ?
cofactors in energy metabolism
| participate in DNA and RNA metabolism
90
what are the three main signs of water soluble vitamin deficiency?
premature fatigue, unable to maintain heavy training, slow wound healing
91
why dont water soluble vitamins usually cause toxicity?
because body doesn't store them
92
which vitamin deficiency can cause lip sores ?
riboflavin
93
which vitamin deficiency causes beriberi ?
thiamin
94
what is the main role of vit B?
form coenzymes
95
what is the main role of vit C
antioxidant
96
what two things does vit C increase
collagen formation and iron absorption
97
which vitamin is crucial for protein metabolism ?
B6
98
which 3 vitamins crucial for glycogen metabolism?
thiamin, niacin, B6
99
what is another word for B6 ?
pyridoxine
100
which 5 vitamins are precursors to CoA?
riboflavin, niacin, thiamin, panthothenic acid, biotin
101
which two vitamins are involved in redox reactions in TCA cycle ? how ?
niacin: NAD, NADP
riboflavin: FAD, FMN
102
what are the three consequences of vit C excess ?
diarrhea, urinary stone formation, impaired copper absorption
103
what is vit C deficiency called ? what are 3 symptoms ?
scurvy
bleeding gums, infections, slow wound healing
104
what muscle pain reflects thiamin (B1) deficiency?
pain in calf muscles
105
what are 4 main symptoms of thiamin deficiency
mental confusion
pain in calf muscles
muscle weakness
nerve degeneration
106
where is Beriberi more common and why
Asia, because thiamin found in husk of rice which they remove
107
how long does a thiamin deficiency have to be left untreated for it to cause serious damage ?
10 days
108
what are the two types of Beriberi
dry and wet
dry affects the PNS
wet affects the cardiovascular system, etc
109
what are the symptoms of dry beriberi
emaciation
| damaged nerves, paralysis
110
what is an early sign of beriberi
paresthesia (tickling, numbness in limbs)
111
what are the symptoms of wet beriberi
dyspnea, edema, etc
112
what condition can affect thiamin deficiency?
alcoholism
113
what are two causes of niacin deficiency ?
alcoholism, PEM
114
what is a visible sign of niacin deficiency ?
glossitis, angular cheliosis
115
what is the niacin deficiency disease and its 4 symptoms
Pellagra
DIarrhea, Dermatitis, Dementia, Death
116
at what point of excess does a niacin toxicity show and how ?
x10 RDA
flushing of skin around face and neck
117
which vitamin are vegans at the most risk of deficiency of ?
B12
118
which B vitamin is the only one not to be found in all foods ?
B12 (mostly in meat)
119
true or false: most B vitamins can be found in all food groups
true
120
what are the two sources of niacin ?
food and body tryptophan
121
which molecule forms niacin in the body
tryptophan
122
what kind of intake is needed for a mineral to be considered major or minor ?
major >100mg
| minor <100 mg
123
why is it easy to get a mineral toxicity from supplements ?
because minerals are tougher to flush out than vitamins
124
does the GI tract absorb more minerals than vitamins ?
no
125
what are three molecules which affect mineral absorption ?
fiber
phytates
tannins
(bind to minerals)
126
what would you recommend to an anemic who has osteoporosis ?
to take iron and calcium supplements together because iron competes with calcium
127
what is the main factor affecting mineral absorption ?
bioavailability
128
what happens to minerals in the blood
go to tissues, or are chelated (bound) by plasma proteins
129
what are 4 things which increase mineral bioavailability
deficiency (an anemic can absorb more iron)
cooking (beta-carotene)
vitamin C
vitamin D
130
which two vitamins increase mineral bioavailability
vit C and vit D
131
which 4 things decrease mineral bioavailability
binders (phytates and oxalates)
high supplement doses of a mineral (limited capacity of absorption)
polyphenols (tannin)
high fiber diet
132
which 4 minerals are involved in muscle contraction ?
calcium
potassium
phosphorus
sodium
133
what are the roles of calcium ?
bone and teeth formation
muscle contraction
nerve impulse transmission
134
what are the 3 effects of calcium deficiency ?
osteoporosis
impaired muscle contraction
muscle cramps
135
what is the effect of excess chlorine and with what compound especially in combination ?
chlorine + sodium = hypertension in excess
136
what is the main role of chlorine ?
hydrochloric acid formation in stomach
137
what is the main role of magnesium ?
bone component
138
what is the main role of potassium ?
membrane potential, muscle contraction
139
what is the main role of phosphorus ?
bone formation and muscle contraction
140
what are the two main roles of sodium ?
muscle contraction and blood volume homeostasis
141
which mineral is responsible for acid-base balance ?
sulfur
142
which mineral has an RDA, not an AI anymore ? what is it ?
calcium
| 1000 mg/day
143
what is the role of copper
iron absorption
144
B12 combines with what mineral for RBC formation ?
cobalt
145
what does fluorine do ?
teeth formation
146
which mineral is a precursor to T3 and T4
iodine
147
which mineral transports oxygen
iron
148
what is the role of selenium ?
antioxidant in cofactor with glutathione peroxidase
149
a goiter occurs from which deficiency ?
iodine
150
supplementation of minerals should not exceed what
2x RDA
151
are losses in minerals in sweat, feces, urine negligible ?
no, have to replace
152
minerals can be found in animals apart from which two ?
iodine and manganese
153
what are the 4 minerals and 3 vitamins which help with building ?
calcium, magnesium, phosphorus, fluorine
vit D, vit K, vit C
154
how do vit D, K, C help with bone formation
vit D increases calcium absorption, increases osteocalcin
vit K activates osteocalcin (bone formation
vit C increases collagen formation
155
what happens with low blood calcium ?
bone demineralization
| Ca mobilized and brought to blood
156
what happens with high blood calcium ?
blood gives calcium to bone (mediated by calcitonin and vit D, increase calcium uptake, increase in osteoblasts, etc and then PTH and osteoclasts)
gives calcium to kidneys too, excrete in urine and reabsorb if needed
157
is calcium proportional to energy intake
yes
158
what is the female triad ?
low energy
amenorrhea
osteoporosis
159
what three vitamins and 4 minerals are antioxidant
C, E, A (beta carotene)
selenium
copper
manganese
zinc
160
what is an antioxidant
donate electron to free radical
161
what is ROS ? what does it do
reactive oxidant species or free radical
| leads to lipid peroxidation
162
what produces ROS ?
alcohol, smoking, UV light, normal cell metabolism, oversupplementation of minerals
163
which diet produces ROS
high fat diet
164
which two enzymes come in and destroy ROS ?
superoxide dismutase and catalase
165
what happens when there are too many free radicals ?
antioxidant cascade: antioxidants become free radicals themselves aided by reductase and peroxidase
166
what is the argument for supplementing antioxidants in exercise ?
exercise increases ROS in skeletal muscle
167
why is it bad to supplement with antioxidants in exercise to suppress ROS ?
because ROS may be a signalling molecule and aid in training adaptations
168
why may it be unnecessary to supplement with antioxidants ?
because training activates antioxidant defense
regular exercise decreases disease risk
megadoses may cause toxicity
and a balanced diet will give you sufficient intake
169
what delivers iron to tissues ?
transferrin
170
iron goes to which 4 places ? why ?
muscle (to form myoglobin)
bone (to form hemoglobin and RBC)
liver (for storage)
tissues (to make heme)
171
what is the molecule which mostly binds to iron ?
ferritin
172
what happens to most iron ?
it is recycled to make new RBC or is stored
| some is lost
173
what is heme ?
iron-containing portion of Hb and Mb
174
what are 2 factors influencing iron absorption ?
iron status
GI function
type of iron source
nutrient interactions
175
in what iron status will you be able to absorb more iron ?
low iron status (so anemics can absorb more)
176
how does GI function affect iron absorption ?
low gastric acid means less iron absorption
| acids help dissolve iron
177
how does type of iron source influence iron absorption ?
heme iron (Fe2+) is more readily absorbed, found in meat and animal products
non-heme (Fe3+) mainly in plants
178
how can you enhance non-heme iron absorption ?
consume vit C-rich foods
| consume heme iron foods (animal meat)
179
which factos decrease iron absorption (6)
polyphenols (tannins in tea and coffee)
oxalates (in spinach, chocolate)
phytates (grains and legumes)
excess fiber
soy
high intakes of micronutrients
180
which sex is more likely to develop an iron deficiency
women
181
what are the three stages of iron deficiency ?
1) iron depletion in bone marrow, with a reduced plasma ferritin concentration of under 12 ug/L and no physical symptoms
2) erythropoeisis decrease and decrease in heme production but RBC and Hb still normal
decrease in work capacity and physical performance
3) anemia : RBC and Hb abnormal
182
what do you call the RBC in anemia
microcytic and hypochromic
183
in anemia, how low is Hb ?
<120g/L
184
in anemia, how low is hematocrit ?
<36%
185
what are symptoms of iron deficiency anemia ?
pale skin, low energy, etc
186
what is the first thing you should do when you suspect anemia ?
get checked BEFORE getting supplements
187
which athletes are at a highest risk of anemia (3)
females
distance runners
vegetarian athletes
188
excess iron reduces which absorption ?
Zn and Cu
189
why should you usually not be concerned about having iron in diet ?
because energy intake is correlated with iron
190
what percentage of iron goes to storage
25 %
191
does anemia change VO2max ?
yes, decreases it
192
what is B12 called
cobalamin
193
what is the structure of B12 ?
corrinoid compound: ring structure with cobalt in the middle
194
what is the function of B12 ? (4)
DNA synthesis
myelin sheath
FA oxidation
convert homocysteine to methionine to decrease CVD risk
195
which two vitamins are active in DNA synthesis ?
folate and B12
196
how does B12 decrease CVD risk
convert homocysteine to methionine
197
why does it take a while to spot a B12 deficiency?
because liver stores are food for 2 years, so symptoms may not appear to up to 12 years
198
what population is mostly at risk of B12 deficiency ?
vegan
| old
199
what are the two food sources of vitamin B12 ?
animal products
| fortified foods
200
what is the function of folate ?
DNA synthesis and cell division
eg prevents neural tube defects during pregnancy and also aids in maturation of RBC
201
increase of folate may mask which deficiency
B12
202
which foods are a food source of folate ?
chicken, grains
203
what are the 4 micronutrients of concern (1 vitamin and 3 minerals) for vegetarians
B12
iron, calcium, zinc
204
are megadoses helpful ?
no evidence that it is helpful
205
which 3 athletes need monitoring and for what ?
young athletes in sports that need low body weight (Ca and Fe)
amenorrheic females (Ca)
train and compete in hot environments (losses in sweat of Fe, Zn, Mg)
206
which liquid should one avoid if you want to get more iron in you
tea
207
what is the main reason for micronutrient insufficiency ?
poor diet (insufficient kcal)
208
what is another word for vit C
ascorbic acid
209
should amenorrheic females take Ca supplements ?
yes
