Water Soluble

Question 1

Thiamin/B1

Answer 1

Metabolized into thiamin pyrophosphate; TCA and nerve impulses.

Deficiency: Beriberi (polished rice diet). Mental confusion, ataxia (abnormal gait), ophthalmoplegia. Wernicke-Korsakoff Syndrome. Common in elderly and alcoholics.

Sources: meats, grain, legumes, fortified food

Question 2

Riboflavin/B2

Answer 2

Metabolized into FAD and FMN (flavins); redox reactions.

Deficiency: angular cheilitis (fissuring at corners of mouth), glossitis (smooth and purplish tonge), and scaly dermatitis. Rare to develop deficiency.

Sources: milk, eggs, liver, green leafy vegetables, fortified food

Question 3

Niacin/B3

Answer 3

Metabolized into NAD+/NADP+; redox reactions.

Deficiency: pellagra (3d’s: dermatitis, diarrhea, dementia). Rare to develop but alcoholics can get it.

Sources: meats, grains, fortified food, can be made from tryptophan

Was used to treat hyperlipidemia but proven to have no benefit.

Question 4

Pyridoxine/B6

Answer 4

Metabolized into pyridoxal phosphate; transamination, deamination, decarboxylation, condensations. Amino acid and glycogen catabolism, neurotransmitter metabolism, myelin synthesis, heme biosynthesis, and conversion of tryptophan to niacin.

Deficiency: peripheral neuropathy, sideroblasstic anemia, lethargy. Rare to develop deficiency.

Women on oral contraceptives need double RDA

Sources: meats, grains.

Question 5

Pantothenic Acid

Answer 5

Metabolized to Coenzyme A and phosphopanthotheine (fatty acid prosthetic group); functions as CoA in acyl transfers.

Deficiency: Rare - no recognized disease.

Sources: livers, eggs, milk

Question 6

Biotin

Answer 6

Food intake as linked biotin (biocytin) which has to be metabolized into biotin; carboxylation (adds CO2 groups)

Deficiency: dermatitis, anorexia, muscle pain, glossitis, nausea etc but very very rare to get deficiency (had to experimentally induced). Can get deficiency from excessive consumption of eggs white (avidin protein).

Sources: 1/2 by diet and 1/2 produced by intestinal flora.

Question 7

Cobalamin/B12

Answer 7

Ingested as hydroxy-cobalamin or OTC as cyano-cobalamin. Metabolized into active forms: adenosyl cobalamin or methyl cobalamin. Adsorption requires Intrinsic Factor from the gut.

Deficiency: slow to develop since body stores for 6-12 years. Causes irreversible neurological damage and pernicious anemia. Most commonly caused by destruction of gastric parietal cells (no IF being produced). Common in elderly.

Sources: meat an dairy (plants don’t require B12 and contain have any; only certain bacteria in the gut can)

Question 8

Folic Acid

Answer 8

found in nature as up to 7 bound glutamic acid residues but humans can only absorb the monoglutamate form. Gut bacteria turn poly form into mono form by conjugase enzyme, which is absorbed and transported to cells, and then turned back into the poly form and tetrahydro form. 1-carbon carrier.

If reaction from homocysteine to methionine is blocked by B12 deficiency, Folic Acid is trapped in methyl form –> methly-folate trap–>interferes with nucleic acid synthesis and can cause anemia.

Needs: 400 micrograms daily
Deficiency: Anemia. Easiest vitamin to become deficient in. Alcoholics are frequently deficient. Can cause neural tube defects in pregnant women.

Sources: green leafy vegetables, liver, nuts, legumes, orange juice, fortified foods.

Question 9

Vitamin C

Answer 9

Ingested in its active form. Coenzyme in hydroxylation of proyl and lysyl residues in collagen, iron adsorption, water-soluble antioxidant, may prevent senile cataracts.

Needs: 60 mg daily
Deficiency: scurvy (sore gums, loose teeth, fragile blood vessels, swollen joints, anemia etc).
Special needs: Smoking, oral contraceptives, and corticosteroids lower serum levels.

Sources: citrus fruits, tomatoes, potatoes, green vegetables.