Water Soluble Vitamins

1. Water Soluble Vitamins Susan Algert

2. Water Soluble Vitamins Thiamin Pantothenic Acid Riboflavin Biotin Niacin Vitamin C Vitamin B-6 Folate Vitamin B-12

3. Fat vs. Water Soluble Vitamins

4. Water soluble vitamins • Susceptible to heat • Kidney removes and excretes excess • Vitamin C, thiamin and riboflavin are especially susceptible to heat and alkilinity • Hydrophilic and water will leach them from vegetables • Preferred methods are steaming, stir-fry and microwave

5. B vitamins act as co-enzymes

6. Thiamin • Sulfur containing and nitrogen containing rings attached to carbon atoms • Part of nerve cell membranes—synthesize and regulate neurotransmitters • Functions in energy metabolism—vitamin portion of TPP; plays role in decarboxylation and helps form Acetyl Co A from pyruvate

7. Thiamin • Dietary Recommendation RDA for adult men is 1.2 mg for women is 1.1 mg per day Higher needs in pregnancy; most diets with variety and adequate energy supply ample thiamin

8. Thiamin • Deficiency • Heavy alcohol consumption with inadequate food consumption ; alcohol interferes with absorption (Wernicke-Korsakoff syndrome); poor and elderly at risk for not eating sufficient energy

9. Thiamin Deficiency/Toxicities • Beri Beri • Impaired muscle contractions • Impaired cardiac function, edema and muscle twitches • Decreased neurological function and memory loss

10. Thiamin food sources • Pork • Whole and enriched grains • Fortified cereals • Most animal foods contain little thiamin

11. Riboflavin • Involved in energy metabolism; part of two co-enzymes, FMN and FAD • Participate in citric acid cycle and beta oxidation and electron transport • Remove ammonia during deamination of some amino acids • Associated with antioxidant glutathione peroxidase

12. Dietary Recommendations for Riboflavin • RDA is 1.1 mg for women and 1.3 mg for men per day • Pregnancy and lactation increase energy needs and need for riboflavin

13. Food Sources • Most plant and animal foods • Milk and milk drinks and yogurt supply about 15% in the American diet • Fortified cereals, bread and bread products contribute about 10% • One of four vitamins added to enriched products

14. Deficiency/Toxicity • Deficiencies are rare although some people may take in marginal amounts • Drug and alcohol users and restricted caloric intake • Ariboflavinosis • Toxicity– not observed

15. Niacin (Nicotinic Acid) • Made from tryptophan; essential nutrient if protein intake is inadequate • 60 mg tryptophan converts to 1 mg niacin • RDA is 14-16 NE/day for adults • NE include preformed and niacin derived from tryptophan

16. Functions of Niacin • NAD and NADP play key role in oxidation-reduction reactions • Helps convert pyruvate to lactate • Coenzyme component that participates in over 200 metabolic reactions

17. Food Sources • Preformed niacin from meat, poultry fish and enriched or whole grain products • Beef and processed meats are substantial contributors in U.S. diet • Stable when heated • Tryptophan found in protein rich animal foods

18. Niacin deficiency • Pellagra • Epidemic in southwest in early 1900’s as corn became staple; niacin is bound by protein • Deficiencies found in southeast if subsisting on diet of corn, molasses and salt pork • International health issue

19. Medicinal uses of niacin • Lowers blood levels of LDL cholesterol • Raises HDL cholesterol • Doses of 1,300 mg to 3,000 mg per day • Side effects include liver abnormalities • UL for niacin is 35 mgms per day • Taken only under medical supervision

20. Biotin • Function critical in energy metabolism ; TCA cycle and gluconeogenesis • Bound to enzymes as a co-factor and requirement is small • No RDA; AI is 30 micrograms/day • Deficiency rare and toxicity not seen

21. Pantothenic Acid • Component of Co enzyme A; involved in energy metabolism • No RDA; AI is 5 mg/day • Deficiency is rare (dermatitis, hair loss, depression) • Toxicity is rare

22. Vitamin B-6 • Forms include pyridoxal, pyridoxine, and pyridoxamine and phosphorylated forms • Functions include support of over 100 different enzyme reactions including : transfer of amino group, carboxyl group or water Enzymes support protein metabolism, blood cell synthesis, CHO metabolism, neurotransmitter synthesis

23. Dietary Recommendations and Sources • RDA is 1-3 mg/day; TUL =100 mg/day • Deficiency symptoms include weakness, insomnia, depression, irritability • Sources include fortified cereals, meat, fish, poultry, starchy vegetables and noncitrus fruits • Heat sensitive; most people get enough

24. B6 Toxicity and Medicinal Use • Megadoses of up to 2,000 mg/day can cause irreversible nerve damage • Large doses used to treat PMS or in stress formulas • UL is 100 mg/day • High doses taken only under medical supervision

25. Folate • Converts vitamin B-12 to coenzyme form • Supports DNA synthesis and cell replication and growth • Along with B12 and B6, may decrease risk for heart disease • Tetrahydrofolic acid (THFA) is coenzyme with five active forms

26. Dietary Recommendations and Deficiency • RDA is 400ug/day (is it most prevalent vitamin deficiency?) • TUL is 1000 ug/day • Deficiency causes macrocytic anemia, NTD • Toxicity masks vitamin B12 deficiency • Dietary folate equivalents= higher bioavailability of supplemental folate vs. folate in foods

27. Folate in foods • Fortified ready to eat cereals • Dark green leafy vegetables • Asparagus • Broccoli • Orange juice • Wheat germ • Legumes

28. Vitamin B-12-Cyanocobalamin • Cobalamin or cobalt containing compounds • Transfers methyl group from folate coenzyme THFA to make active form; B12 deficiency leads to folate deficiency • Dietary recommendations 2.4 ugm/day for men and women • Atrophic gastritis decreases bioavailability in adults over 51

29. Vitamin B-12 Absorption • R-protein • pancreatic enzymes • Intrinsic factor • Bacteria in the stomach • Gastric acid production

30. B12 in the diet • RDA is 2.4 ugm per day; B12 not present in plant foods • Animals store excess B12 in tissues • Mixed foods with animal protein contribute most B12 • B12 deficiency usually occurs due to impaired absorption • Vegans at risk

31. Deficiency disease is pernicious anemia • Megaloblasts and macrocytes rather than normal red blood cells • Brain abnormalities and spinal cord degeneration which can be lethal • Pernicious anemia attacks parietal cells and diminishes intrinsic factor and stomach acid

32. Functions of Vitamin C • Antioxidant—donates electron minimizing free radical damage; Recycles oxidized vitamin E for reuse • Collagen synthesis • Stabilizes reduced form of folate enzyme • Enhances absorption of non-heme iron • Helps synthesize carnitine • Proper functioning of immune system

33. Vitamin C deficiency/toxicity • Scurvy • Breakdown gums and joints • Bone pain, diarrhea, fractures, fatigue • UL is 2,000 mg per day • Can possibly enhance oxidation when consumed in high doses without other antioxidants

34. Dietary Recommendations • RDA is 90 mg for men and 75 mg for women per day • Smokers require +35 mg per day • Food sources include potatoes, citrus fruits, broccoli, leafy greens • Highly vulnerable to heat and oxidation

35. Vitamin like compounds • Choline • Inositol • Carnitine • Lipoic acid