2. Vitamins Vital amines – “vital to life” (1900s) Their deficiency attests to their importance Three new columns added to the Vitamins table on the web http://www.iom.edu/Object.File/Master/7/296/0.pdf http://arbl.cvmbs.colostate.edu/hbooks/pathphys/mis c_topics/vitamins.html

3. The Vitamins They are organic non-energy yielding, micronutrients. They are necessary for normal metabolism in animals. They either are not synthesized in the body or are synthesized in inadequate quantities. Hence they are essential nutrients (Vitamin D is an exception). Most vitamins function as coenzymes or cofactors. Deficiency states are recognized for all vitamins, and in many cases, excessive intake also leads to disease. Copyright 2005 Wadsworth Group, a division of Thomson Learning

4. The Vitamins Vitamins vs carbohydrates, fats, and proteins –Structure (organic) They are not macromolecules made by linking individual units –Function (non-energy yielding) Do not provide usable energy They are required to help the various enzymes in the body some of which help to release the energy from food –Food contents (micronutrients) Amounts in food and amounts required are measured in micrograms (as opposed to grams and milligrams for other nutrients) Copyright 2005 Wadsworth Group, a division of Thomson Learning

5. The Vitamins Bioavailability –Amount of vitamin available in foods: Amount in food Amount absorbed and used by the body –Determined by Efficiency of digestion Time to go through GI tract Previous nutrient intake and nutrition status Other foods consumed at the same time –E.g. alcohol inhibits thiamin absorption Method of food preparation (raw, cooked or processed) –Some vitamins may get leached out if cooked into too much water –Some vitamins are inactivated by high heat Source of nutrient –Synthetic –Fortified –Naturally occurring Copyright 2005 Wadsworth Group, a division of Thomson Learning

6. The Vitamins Precursors –Some vitamins are available in foods as precursors –Necessary to measure amount of active vitamin plus potential amount available from precursors E.g. tryptophan is a precursor for Niacin 1 mg of Niacin required 60mg of dietary tryptophan So recommended intakes are in Niacin equivalents (NE) Organic nature –Can be destroyed by heating, UV rays (sun) or fluorescent light (Riboflavin) –Can be destroyed by oxidation (Vitamin C) cut fruits, fruit juices –Table 10-1 “ Minimizing nutrient losses” Refrigerate, wash before cutting, use microwave oven or steam in small amount of water, cook for short time, low temperature Copyright 2005 Wadsworth Group, a division of Thomson Learning

7. The Vitamins Solubility –Hydrophilic (water soluble) B Vitamins and Vitamin C –Hydrophobic (fat soluble) Vitamins A, D, E and K Toxicity –More is not necessarily better Copyright 2005 Wadsworth Group, a division of Thomson Learning

8. The Vitamins Copyright 2005 Wadsworth Group, a division of Thomson Learning

9. The Vitamins Copyright 2005 Wadsworth Group, a division of Thomson Learning

10. The Water-Soluble Vitamins B Vitamins and Vitamin C Copyright 2005 Wadsworth Group, a division of Thomson Learning

11. Metabolic Pathways Involving B Vitamins Niacin B6B6 Thiamin Riboflavin Pantothenic acid Folate Riboflavin

12. The B Vitamins Coenzymes Copyright 2005 Wadsworth Group, a division of Thomson Learning

13. Thiamin Copyright 2005 Wadsworth Group, a division of Thomson Learning Other names: Vitamin B 1 1998 RDA –men: 1.2 mg/day –women: 1.1 mg/day Chief functions in the body –Part of coenzyme TPP (thiamin pyrophosphate) used in energy metabolism –Required for the breakdown of glucose to release energy –Required for the functioning of the nervous system, especially the peripheral nerves, like those found in your hands and feet –Vital for adequate muscle coordination

14. Thiamin Significant sources –Whole grain, fortified, or enriched grain products –Moderate amounts in all nutritious food –Pork Easily destroyed by heat Copyright 2005 Wadsworth Group, a division of Thomson Learning

16. Thiamin Copyright 2005 Wadsworth Group, a division of Thomson Learning Deficiency disease –Beriberi Wet, with edema Dry, with muscle wasting Deficiency symptoms –Enlarged heart, cardiac failure –Muscular weakness –Apathy, poor short-term memory, confusion, irritability –Anorexia, weight loss Toxicity symptoms: none reported

17. Riboflavin Copyright 2005 Wadsworth Group, a division of Thomson Learning

18. Riboflavin Other names: Vitamin B 2 1998 RDA –Men: 1.3 mg/day –Women: 1.1 mg/day Chief functions in the body –Part of coenzymes FMN (flavin mononucleotide) and FAD (flavin adenine dinucleotide) –These coenzymes are used in energy-yielding metabolic pathways from both glucose and fatty acids –Metabolism of certain vitamins and minerals also requires Riboflavin Copyright 2005 Wadsworth Group, a division of Thomson Learning

19. Riboflavin Significant sources –Milk products (yogurt, cheese) –Enriched or whole grains –Liver Easily destroyed by ultraviolet light and irradiation Copyright 2005 Wadsworth Group, a division of Thomson Learning

21. Riboflavin Copyright 2005 Wadsworth Group, a division of Thomson Learning Deficiency disease: ariboflavinosis Deficiency symptoms –Inflamed eyelids and sensitivity to light, reddening of cornea –Sore throat –Cracks and redness at corners of mouth –Painful, smooth, purplish red tongue –Inflammation characterized by skin lesions covered with greasy scales Toxicity symptoms: none reported

22. Niacin Copyright 2005 Wadsworth Group, a division of Thomson Learning Other names –Nicotinic acid –Nicotinamide –Niacinamide –Vitamin B 3 Precursor: dietary tryptophan 1998 RDA –Men: 16 mg NE/day –Women: 14 mg NE/day Upper level for adults: 35 mg/day

23. Niacin Chief functions in the body –Part of coenzymes NAD (nicotinamide adenine dinucleotide) and NADP (its phosphate form) used in energy metabolism Significant sources –Milk, eggs, meat, poultry, fish –Whole-grain and enriched breads and cereals –Nuts –All protein-containing foods Copyright 2005 Wadsworth Group, a division of Thomson Learning

25. Niacin Copyright 2005 Wadsworth Group, a division of Thomson Learning Deficiency disease: pellagra Deficiency symptoms –Diarrhea, abdominal pain, vomiting –Inflamed, swollen, smooth, bright red tongue –Depression, apathy, fatigue, loss of memory, headache –Bilateral symmetrical rash on areas exposed to sunlight Toxicity Symptoms –Painful flush, hives, and rash (“niacin flush”) –Excessive sweating –Blurred vision –Liver damage, impaired glucose tolerance

26. Biotin 1998 adequate intake (AI) –Adults: 30 g/day Chief functions in the body –Part of a coenzyme used in energy metabolism, fat synthesis, amino acid metabolism, and glycogen synthesis Significant sources –Widespread in foods –Organ meats, egg yolks, soybeans, fish, whole grains –Raw egg yolks have avidin which binds up biotin making it unavailable –Also produced by GI bacteria Copyright 2005 Wadsworth Group, a division of Thomson Learning

27. Biotin Copyright 2005 Wadsworth Group, a division of Thomson Learning Deficiency –Rare –Seen in adults that are fed artificially by vein without biotin supplementation –Caused by long term alcohol abuse –Can be induced by feeding people raw eggs (avidin) Deficiency symptoms –Depression, lethargy, hallucinations, numb or tingling sensation in the arms and legs –Red, scaly rash around the eyes, nose, and mouth –Hair loss Toxicity symptoms: none reported

28. Pantothenic Acid Copyright 2005 Wadsworth Group, a division of Thomson Learning 1998 adequate intake (AI) –Adults: 5 mg/day Chief functions in the body –Part of coenzyme A, used in energy metabolism Significant sources –Widespread in foods –Organ meats, mushrooms, avocados, broccoli, whole grains Easily destroyed by food processing

29. Pantothenic Acid Copyright 2005 Wadsworth Group, a division of Thomson Learning Deficiency symptoms –Vomiting, nausea, stomach cramps –Insomnia, fatigue, depression, irritability, restlessness, apathy –Hypoglycemia, increased sensitivity to insulin Toxicity symptoms: none reported

30. Vitamin B 6 Copyright 2005 Wadsworth Group, a division of Thomson Learning Other names –Pyridoxine –Pyridoxal –Pyridoxamine 1998 RDA –Adults (19-50 years): 1.3 mg/day Upper level for adults: 100 mg/day Stored extensively in muscle tissue (unlike other water soluble vitamins)

31. Vitamin B 6 Copyright 2005 Wadsworth Group, a division of Thomson Learning Chief functions in the body –Part of coenzymes PLP (pyridoxal phosphate) and PMP (pyridoxamine phosphate) used in amino acid and fatty acid metabolism –Helps to convert tryptophan to niacin and to serotonin –Helps to make red blood cells –Influences cognitive performance, immune function and steroid hormone activity

32. Vitamin B 6 Significant sources –Meats, fish, poultry –Potatoes, legumes, noncitrus fruits –Fortified cereals –Liver –Soy products Deficiency symptoms –Scaly dermatitis –Anemia (small-cell type) –Depression, confusion, abnormal brain wave pattern, convulsions –One cause is INH (TB drug) Copyright 2005 Wadsworth Group, a division of Thomson Learning

33. Vitamin B 6 Copyright 2005 Wadsworth Group, a division of Thomson Learning Toxicity symptoms –Depression, fatigue, irritability, headaches –Nerve damage causing numbness and muscle weakness leading to an inability to walk and convulsions –Skin lesions

34. Copyright 2005 Wadsworth Group, a division of Thomson Learning

35. Folate Absorption Folate is absorbed efficiently from fortified products Too much folate Copyright 2005 Wadsworth Group, a division of Thomson Learning

36. Folate Absorption –Folate is absorbed efficiently from fortified products –Neural tube defects (spina bifida) in babies born to women with folate deficiency –Deficiency takes effect early on in pregnancy –So all women of child bearing age are advised to take folate supplements Copyright 2005 Wadsworth Group, a division of Thomson Learning

37. Folate Activation –Vitamin B 12 Copyright 2005 Wadsworth Group, a division of Thomson Learning

38. Folate Recommendations –Dietary folate equivalents (DFE) Copyright 2005 Wadsworth Group, a division of Thomson Learning

39. Folate Neural tube defects –Spina bifida Copyright 2005 Wadsworth Group, a division of Thomson Learning

40. Folate Heart disease –High levels of homocysteine and low levels of folate Cancer Copyright 2005 Wadsworth Group, a division of Thomson Learning

41. Folate: In Summary Copyright 2005 Wadsworth Group, a division of Thomson Learning Other names –Folic acid –Folacin –Pteroylglutamic acid (PGA) 1998 RDA –Adults: 400 g/day Upper level for adults: 1000 g/day

42. Folate: In Summary Copyright 2005 Wadsworth Group, a division of Thomson Learning Chief functions in the body –Part of coenzymes THF (tetrahydrofolate) and DHF (dihydrofolate) used in DNA synthesis and therefore important in new cell formation Significant sources –Fortified grains –Leafy green vegetables, legumes, seeds –Liver

43. Folate: In Summary Copyright 2005 Wadsworth Group, a division of Thomson Learning Deficiency symptoms –Anemia (large-cell type) –Smooth, red tongue –Mental confusion, weakness, fatigue, irritability, headache Toxicity symptoms –Masks vitamin B 12 -deficiency symptoms

44. Folate Sources Copyright 2005 Wadsworth Group, a division of Thomson Learning

46. Vitamin B 12 Activation –Folate Copyright 2005 Wadsworth Group, a division of Thomson Learning

47. Vitamin B 12 Absorption –HCl –Pepsin –Intrinsic factor Copyright 2005 Wadsworth Group, a division of Thomson Learning

48. Vitamin B 12 Deficiency of folate or B 12 produces pernicious anemia Copyright 2005 Wadsworth Group, a division of Thomson Learning

49. Vitamin B 12 : In Summary Copyright 2005 Wadsworth Group, a division of Thomson Learning Other names: cobalamin (and related forms) 1998 RDA –Adults: 2.4 g/day Chief functions in the body –Part of coenzymes methylcobalamin and deoxyadenosylcobalamin used in new cell synthesis –Helps to maintain nerve cells –Reforms folate coenzyme –Helps to break down some fatty acids and amino acids

50. Vitamin B 12 : In Summary Copyright 2005 Wadsworth Group, a division of Thomson Learning Significant sources –Animal products (meat, fish, poultry, shellfish, milk, cheese, eggs) –Fortified cereals Easily destroyed by microwave cooking Deficiency disease: pernicious anemia

51. Vitamin B 12 : In Summary Copyright 2005 Wadsworth Group, a division of Thomson Learning Deficiency symptoms –Anemia (large-cell type) –Fatigue, degeneration of peripheral nerves progressing to paralysis Toxicity symptoms: none reported

52. Non-B Vitamins Choline Copyright 2005 Wadsworth Group, a division of Thomson Learning

53. Non-B Vitamins Inositol –Cell membrane structure Carnitine –Transports long chain to the mitochondria for oxidation Vitamin imposters –Many of these are included in Vitamin supplements –Unnecessary since they are available in foods Copyright 2005 Wadsworth Group, a division of Thomson Learning

54. Metabolic Pathways Involving B Vitamins

55. The B Vitamins B vitamin deficiencies –Glossitis –Cheilosis B vitamin toxicities B vitamin food sources Copyright 2005 Wadsworth Group, a division of Thomson Learning

56. Vitamin C Copyright 2005 Wadsworth Group, a division of Thomson Learning

57. Vitamin C Copyright 2005 Wadsworth Group, a division of Thomson Learning Other name: ascorbic acid 2000 RDA –Men: 90 mg/day –Women: 75 mg/day –Smokers: + 35 mg/day Upper level for adults: 2000 mg/day

58. Vitamin C Copyright 2005 Wadsworth Group, a division of Thomson Learning Chief functions in the body –Collagen synthesis Strengthens blood vessel walls, forms scar tissue, provides matrix for bone growth –Antioxidant –Thyroxin synthesis –Amino acid metabolism –Strengthens resistance to infection –Helps in absorption of iron

59. Vitamin C Copyright 2005 Wadsworth Group, a division of Thomson Learning Significant sources –Citrus fruits –Cabbage-type vegetables, dark green vegetables (such as bell peppers and broccoli) –Cantaloupe, strawberries –Lettuce, tomatoes, potatoes –Papayas, mangoes Easily destroyed by heat and oxygen

60. Vitamin C Sources Copyright 2005 Wadsworth Group, a division of Thomson Learning

62. Vitamin C Copyright 2005 Wadsworth Group, a division of Thomson Learning Deficiency disease: scurvy Deficiency symptoms –Anemia (small-cell type) –Atherosclerotic plaques –Pinpoint hemorrhages, bone fragility, joint pain –Poor wound healing, frequent infections, bleeding gums, loosened teeth –Muscle degeneration and pain, hysteria, depression, rough skin, blotchy bruises

63. Vitamin C Copyright 2005 Wadsworth Group, a division of Thomson Learning Toxicity symptoms –Nausea, abdominal cramps, diarrhea –Headache, fatigue, insomnia –Hot flashes, rashes –Interference with medical tests, aggravation of gout symptoms, urinary tract problems, kidney stones

64. Vitamin And Mineral Supplements Arguments for supplements –Correct overt deficiencies –Improve nutrition status –Reduce disease risks –Support increased nutrient needs –Improve the body’s defenses Copyright 2005 Wadsworth Group, a division of Thomson Learning

65. Vitamin And Mineral Supplements Who needs supplements? Copyright 2005 Wadsworth Group, a division of Thomson Learning

66. Vitamin And Mineral Supplements Arguments against supplements –Toxicity –Life-threatening misinformation –Unknown needs –False sense of security –Other invalid reasons Copyright 2005 Wadsworth Group, a division of Thomson Learning

69. Vitamin And Mineral Supplements Bioavailability Antagonistic actions Copyright 2005 Wadsworth Group, a division of Thomson Learning

70. Vitamin And Mineral Supplements Selection of supplements –Form –Contents –Misleading claims –Cost Copyright 2005 Wadsworth Group, a division of Thomson Learning

71. Vitamin And Mineral Supplements Regulation of supplements Copyright 2005 Wadsworth Group, a division of Thomson Learning

72. An Example of a Supplement Label Copyright 2005 Wadsworth Group, a division of Thomson Learning