Under-nutrition (2/19) Flashcards
1
Q
What accounts for over half of the world’s disease burden?
A
malnutrition
2
Q
What is malnutrition?
A
too much food or hunger
3
Q
How many kcals/day does adults need to support healthy life?
A
2100
4
Q
What is hidden hunger?
A
micronutrient deficiencies
5
Q
What does under-nutrition do?
A
physical and mental activity declines, growth slows and ceases altogether, muscle & fat wasting occurs, the immune system weakens, death rates rise
6
Q
What are health consequences of undernutrition?
A
poor people may eat and absorb too little nutritious food, making them more disease prone; inadequate or inappropriate food leads to stunted development or premature death; nutrient-deficient diets provoke health problems; disease decreases people’s ability to cultivate or purchase nutrient foods; sickness and loss of livelihood
7
Q
What are the complex causes of world hunger?
A
AIDs; rapid depletion of natural resources; poor infrastructure; high external debt; extreme imbalances in the food/population ratio; war and political/civil unrest
8
Q
What is food insecurity?
A
limited or uncertain access to nutritious safe foods necessary to lead a healthy lifestyle
9
Q
What does households that experience food insecurity have?
A
reduced quality or variety of meals and may have irregular food intake
10
Q
What are food insecurities in the US linked to?
A
obesity (especially in women) and higher risk of chronic diseases (e.g, diabetes)
11
Q
What is high household food security?
A
no indications of food access problems or limitations
12
Q
What is marginal household food security?
A
1 or 2 indications of food access problems (anxiety, shortage of food); little or no change in diets or food intake
13
Q
What is low household food security?
A
reduction in quality, variety, desirability of diet; little or no reduced food intake
14
Q
What is very low household food security?
A
multiple indications of disrupted eating patterns and reduced food intake
15
Q
What are the nutrient deficiency diseases that are commonly accompanying undernutrition?
A
xerophthalmia, rickets, beriberi, ariboflavinosis, pellagra, megaloblastic anemia, scurvy, iron deficiency anemia, goiter, protein-energy malnutrition
16
Q
What vitamin deficiency causes xerophthalmia?
A
vitamin A
17
Q
Where is xerophthalmia commonly seen?
A
asia, africa
18
Q
What vitamin deficiency causes rickets?
A
vitamin D
19
Q
Where is rickets commonly seen?
A
asia, africa (due to clothing)
20
Q
What vitamin deficiency causes beriberi?
A
thiamin
21
Q
Where is beriberi commonly seen?
A
areas of famine
22
Q
What vitamin deficiency causes ariboflavinosis?
A
riboflavin
23
Q
Where is ariboflavinosis commonly seen?
A
areas of famine
24
Q
What vitamin deficiency causes pellagra?
A
niacin
25
Where is pellagra commonly seen?
areas of famine
26
What vitamin deficiency causes megaloblastic anemia?
folate
27
Where is megalobastic anemia commonly seen?
asia, africa
28
What vitamin deficiency causes scurvy?
vitamin C
29
Where is scurvy commonly seen?
areas of famine
30
Where is iron deficiency anemia commonly seen?
worldwide
31
What vitamin deficiency causes goiter?
iodine
32
Where is goiter commonly seen?
south america, eastern europe, africa
33
What are vitamins?
organic compounds required by the body in trace amounts that perform specific metabolic funcitons
34
Are vitamins dietary essentials?
yes, they are not synthesized by the body or are not synthesized in sufficient quantity
35
What are the fat soluble vitamins?
ADEK
36
What are the water soluble vitamins?
thiamin, riboflavin, niacin, B6, B12, folic acid, pantothenic acid, biotin, ascorbic acid (C)
37
How do we get vitamin A?
some comes preformed in animal tissues others can be "made" from provitamins found in plant tissue (carotenoids)
38
What is a food that contains both forms of vitamin A?
milk fat and egg yolk
39
What are the 3 forms of vitamin A?
retinol, retinal (all trans), and beta-carotene
40
What are carotenoids?
yellow-orange pigmented materials in fruits and vegetables
41
How is retinoids absorbed?
preformed vit. A in animal foods as retinol and retinyl ester; retinyl ester is hydrolyzed in small intestine to retinol and fatty acid; 90% of retinol is absorbed into the cells of the small intestine via a specific carrier protein and is re-esterified; newly formed retinyl esters are packaged to chylomicrones, enter the lymph circulation, and are delivered to tissues for storage (liver)
42
How much vit. A does the liver store?
enough to last for several months and protect from deficiencies
43
What happens to vitamin A once it is released from the liver?
goes into the bloodstream and is then bound to retinol binding protein (RBP); RBP is attached to transthyretin (TTR) in circulation; RBP and TTR deliver vit. A to cells; vit A is then transferred to one of several cellular retinoid-binding proteins (CRBP) which direct vit. A to functional sites in the cells.
44
How is carotenoids absorbed?
dietary carotenoids are attached to proteins that are then cleaved by digestive enzymes in the small intestine; carotenoids are then absorbed mainly by passive diffusion; inside the intestinal cell, carotenoids are cleaved to form retinal or retinoic acid; retinal is converted to retinol which is re-esterified and transported to the liver. retinoic acid can enter the bloodstream directly for transport to the liver
45
What does nuclear retinoid receptors do?
bind to response elements in DNA, regulate formation of mRNA from vit. A responsive genes, and broad spectrum of functions
46
What are the types of nuclear retinoid receptors?
RXR and RAR
47
What are the physiological functions of vit. A?
visual cycle, maintenance of epithelial tissues, growth/differentiation, reproduction, immunity
48
What is the retinol activity equivalents?
1 RAE = 1 microgram all trans retinol, 12 microgram all trans beta-carotene, or 24 micrograms other carotenoids
49
What is the RDA for vit. A?
900 microgram/day RAE for men and 700 microgram/day RAE for women
50
What is the UL for vit A?
3000 microgram RAE
51
What are vit. A deficiency sympotms?
night blindness, keratinizaiton of epithelial tissue, xerophthalmia, blindness
52
What are acute toxicity symptoms for vit. A?
gastrointestinal upset/nausea, headaches, dizziness, muscle uncoordination
53
What are chronic toxicity symptoms for vit. A?
liver damage, hair loss, bone/muscle pain, loss of appetite, dry skin and mucous membranes, hemorrhages, coma, fractures
54
What are teratogenic toxicity symptoms for vit. A?
fetal malformation and spontaneous abortion
55
What is nyctalopia?
night blindness
56
How does night blindness occur?
blood retinol levels too low to replace retinal in visual cycle, thus rods regenerate rhodopsin more slowly, slower adjustment to low light
57
What is xerosis?
dryness at mucous membrane covering the front surface of the eye
58
What does xerosis progress too?
bitot's spots
59
What are bitot's spots?
foamy gray spots on the eye consisting of hardened epithelial cells
60
What do bitot's spots progress to?
keratomalacia
61
What is keratomalacia?
softening of the cornea and scaring
62
What is xerophthalmia?
irreversible blindness
63
What does keratin do?
protects the inner layers and reduces water loss
64
What is follicular hyperkeratosis?
hair follicles plugged with keratin giving dry, rough, sandy texture to the skin
65
What is keratinizaiton?
low retinoic acid leads to deterioration of mucous-forming cells. keratinized cells replace the normal mucous forming cells
66
What was the international initiative to decrease vitamin A deficiency?
promoting breastfeeding, fortification of foods, educational programs to increase home gardening of vit. A rich foods and veggies, providing vit. A supplements to populations at risk
67
What are symptoms of acute vit A toxicity?
GI upset, nausea, headaches, etc.
68
What are symptoms of chronic vit. A toxicity?
liver damage, hair loss, bone muscle pain, etc.
69
What are symptoms of teratogenic vit. A toxicity?
fetal malformation, spontaneous abortion
70
What needs to come together to form an active enzyme?
inactive enzyme and vitamin coenzyme
71
What is the coenzyme form of thiamin?
thiamin pyrophosphate (TPP)
72
What was the cure for beriberi?
rice polishings
73
how is thiamin absorbed?
through active transport
74
is thiamin needed in the diet daily?
yes, due to only a little being stored
75
how is thiamin excreted?
in urine
76
What energy generating reactions is TPP involved in?
decarboxylation reactions; 20 other reactions in carbs, lipids, and protein metabolism; conversion of tryptophan to niacin
77
What is the RDA for thiamin?
1.2 mg/d for men or 1.1 mg/d for women
78
What are the food sources that we can get thiamin?
pork, legumes, wheat germ, dried yeast, enriched flour and other products
79
What does enriched mean?
thiamin, niacin, riboflavin, and iron added to a grain product to level present prior to processing
80
What does fortified mean?
vitamins and/or minerals added to a food product in excess of what was originally found in the product.
81
What enzyme destroys thiamin?
thiaminase enzyme
82
Where can thiaminase enzyme by found?
some species of fresh fish and shellfish
83
What foods are antagonists for thiamin?
coffee, tea, blueberries, and beets
84
What is beriberi disease?
deficiency of thiamin
85
what is symptoms of beriberi?
anorexia, weight loss, apathy, loss of short-term memory, confusion, irritability, peripheral neuropathy, muscle weakness
86
What is wernicke-korsakoff syndrome?
reduced absorption of thiamin, increased excretion of thiamin, poor diet
87
What are symptoms of wernicke-korsakoff syndrome?
ataxia, deranged, nystagmus
88
What is the coenzyme form of riboflavin?
flavin adenine dicucleotide (FAD)
89
How is riboflavin absorbed?
active transport into intestinal mucosal cells, phosphorylated in mucosal cells, transported to liver, further phosphorylated
90
T/F: riboflavin is not absorbed better with food
false, it is absorbed better
91
What is riboflavin synthesized by?
intestinal bacteria but not known to be absorbed
92
What are riboflavins coenzyme forms?
FMN (flavin mononucleotide) and FAD (flavin adenine dinucleotide)
93
What is the RDA for riboflavin?
1.3 mg/d for men and 1.1 mg/d for women
94
What are the food sources of riboflavin?
milk, organ meats, green leafy vegetables, enriched flour and other products
95
T/F: riboflavin is light sensitive
true
96
What is riboflavin deficiency?
ariboflavinosis
97
What is symptoms of ariboflavinosis?
cheilosis (dry skin around nose and mouth), glossitis, low levels in RBCs
98
What diseases is common with ariboflavinosis?
cancer, CVD, diabetes, alcoholism, malabsorption disorders
99
How is niacin absorbed?
diffusion and active transport in the stomach and small intestine
100
What is niacin converted to in tissues?
NAD+ and NADP+
101
Where are niacin coenzymes stored?
in the liver
102
Where is excess niacin excreted?
in urine
103
What does NAD play a role in?
hydrogen acceptor in glycolysis and citric acid cycle
104
What does NADP play a role in?
hydrogen donor in fatty acid and cholesterol synthesis
105
What is the DRI for niacin?
6.6 mg/1000 kcal
106
What is the RDA for niacin?
16 mg/d for men and 14 mg/d for women
107
What is the UL for niacin?
35 mg/d
108
What are food sources for niacin?
meat, poultry, fish > fruits, veggies, grains > dairy, eggs
109
What disease is caused from niacin deficiency?
pellagra
110
What are symptoms of pellagra?
the 4Ds... dermatitis, diarrhea, dementia, death
111
How was pellagra eradicated in the US?
through enrichment of grains and protein-rich foods
112
When can pellagra be observed today?
in severe malabsorption, chronic alcoholism, Hartnup disease
113
What is hartnup disease?
genetic disorder where tryptophan to niacin pathway is blocked
114
how is folate absorbed?
glutamic acid residues removed in upper intestine and then absorbed immediately
115
What is the rate of absorption of folate reduced by?
increased number of glutamic acid residues
116
What is the function of folate?
transfer of single carbon units (nucleic acid synthesis and some amino acids)
117
What is the coenzyme form of folate?
tetrahydrofolate (THF)
118
What is the RDA of folate?
400 micrograms/d
119
What does the requirement of folate increase with?
increased levels of cell replication (pregnancy, growth)
120
What is food sources of folate?
green vegetables, liver, fish, poultry, legumes
121
What happens with folate deficiency?
megaloblastic anemia and neural tube defects
122
how is cobalamin absorbed?
b12 released by HCl and pepsin in stomach and then combines with R-protein from salivary glands for travel to duodenum, pancreatic proteases free B12 to combine with intrinsic factor which was synthesized in stomach and then travels to ileum where B12 is absorbed by a receptor
123
What transports cobalamin to tissues?
transcobalamin II
124
What are the functions of cobalamin?
single carbon unit metabolism, recycle folate coenzymes, and nervous system function
125
What is the RDA for cobalamin?
2.4 micrograms/d
126
What are food sources of cobalamin?
all of bacterial origin, liver, seafood, meat, eggs, milk
127
What disease does cobalamin deficiency lead to?
pernicious anemia
128
What is pernicious anemia?
lack of intrinsic factor
129
How is vitamin B6 absorbed?
dephosphorylated in intestine, absorbed (by diffusion) and transported in free form to the liver, phosphorylated when enters cells to PLP by pyridoxal oxidase, transported in blood as PLP on albumin, main storage in muscle
130
how is excess B6 excreted?
in urine
131
What functions is B6 involved in?
amino acid metabolism (transamination, decarboxylation, transsulfuration, side chain transfers) and phosphorylase which mobilizes glucose form glycogen, hemoglobin synthesis, neurotransmitter synthesis, tryptophan to niacin
132
what is the RDA for B6?
1.3 mg/d
133
What is the UL for B6?
100 mg/d
134
What are food sources for B6?
yeast, organ meats, whole grains, cereals, legumes, bananas
135
What are antagonists of B6?
antitubercular drugs, antibiotics, oral contraceptive pills
136
What happens with B6 deficiency?
microcytic hypochromic anemia, marginal deficiency, pregnancy and lactation
137
What is microcytic hypochromic anemia?
reduced hemoglobin synthesis, small RBCs, muscle weakness, irritability, depression, confusion, and dermatitis
138
What is the toxicity for B6?
2-6 g/d for 6 months
139
how is ascorbic acid absorbed?
by active transport and diffusion into portal blood
140
how much ascorbic acid is stored in the liver, spleen, and adrenals?
1500 mg
141
how is ascorbic acid excreted?
in urine
142
What is the functions of ascorbic acid?
collagen formation, antioxidant, neurotransmitter synthesis, iron absorption, immune function, cancer prevention
143
What is collagen formation?
conversion of proline and lysine to hydroxyproline and hydroxylysine
144
how much ascorbic acid needed to prevent scurvy?
10 mg/d
145
What is the RDA for ascorbic acid?
90 mg/d for men and 75 mg/d for women
146
What is the UL of ascorbic acid?
2000 mg/d
147
What increases the requirement of ascorbic acid?
smoking
148
What are food sources of ascorbic acid?
citrus fruits, potatoes, green veggies
149
What is scurvy?
abnormal collagen synthesis, fatigue, pinpoint hemorrhage, bleeding gums
150
What are symptoms of ascorbic acid toxicities?
GI disturbances (nausea, cramps, diarrhea) and some questionable symptoms reported with megadoses (kidney stones, excess iron absorption, B12 deficiency, dental enamel erosion, allergic response, etc.)
