Chapter Six – Part 1 The Water Soluble Vitamins NUT SCI 142 © Spring 2005 Karen Lacey, MS, RD, CD I. Overview - History 100 years ago first discovered “vitamin” Deficiency diseases – since early times – Scurvy (Vitamin C) – 1700’s – Rickets (Vitamin D) – 1600’s – Pellegra (Niacin) – 1700’s More recent research – Role in preventing chronic diseases – Antioxidants – Controversy A. Key concepts Provide NO energy Facilitate body processes and reactions that are “VITAL” – – – – – Promote growth and reproduction Healthy nerves and skin Build bones, teeth and blood Heal wounds Help release energy from foods Large amounts can be dangerous B. Categories WATER SOLUBLE (9) – Thiamin (B1) – Riboflavin (B2) – Niacin (B3) – Folate (folic acid) – Vitamin B6 – Vitamin B12 – Pantothenic Acid – Biotin – Vitamin C (ascorbic acid) FAT SOLUBLE (4) – – – – Vitamin A Vitamin D Vitamin E Vitamin K 1. Thiamin Roles – Coenzymes in releasing energy (especially carbohydrates) – Nerve function DRI – 1.1 to 1.2 mg – Based on calories Severe Deficiency – “beriberi” – Extreme muscle wasting, paralysis and heart failure – Mental confusion Mild Deficiency – Mimics other conditions – Vague, HA, fatigue, fever etc Thiamin in Foods No one food meets daily needs Wide variety of foods – – – Pork and ham family Whole-grain and enriched foods Nuts and Legumes Losses with boiling Little to none in “junk” foods that are high in carbohydrates 2. Riboflavin Roles – Coenzymes in releasing energy – Helps prepare fats and amino acids for breakdown – Healthy skin and eyes DRI – 1.1 to 1.3 mg Deficiency – Rare – No disease; symptoms – Skin problems around nose and mouth – Eye problems Riboflavin in Foods Milk and milk products (1/2) Meats Whole-grain and enriched foods Leafy green vegetables Destroyed by UV sun and fluorescent light and irradiation 3. Niacin Roles – Coenzymes in releasing energy – Healthy skin, nerves and digestive system Deficiency – “pellegra” – Skin rash – 4 “D’s” Diarrhea, Dermatitis, Dementia and Death DRI – 14 to 16 mg NE NE = niacin equivalent – Tryptophan can be converted to niacin – 60 mg = 1 mg niacin Drug to lower “LDL” – High doses (500 mg) – Side effects Niacin in Foods Eggs, meat, poultry and fish Whole-grain and enriched breads and cereals Nuts Legumes 4. Folate (folic acid, folacin) Roles – – – – – Coenzyme DNA synthesis Red blood cell formation Protein metabolism New cell division DRI – 400 ug Deficiency – – – Neural tubal defect Anemia Increase risk of cancers and heart disease Folate in foods Fresh vegetables Legumes Fruits; especially citrus Seeds Whole-grain, enriched and fortified foods 5. Vitamin B 6 Roles – – – Protein and fat metabolism Antibodies and red blood cells Requirement proportional to protein intake Roles (cont) – – Converts tryptophan to niacin May help prevent heart disease – decrease homocysteine DRI – 1.3 mg Vitamin B 6 (cont) Deficiency – – – – – If eat a poor diet when needs are higher (ex. pregnancy) Alcohol; increase loss TB drug binds with vitamin Weakness, impaired immune function Increase risk of heart disease Toxicity (2000 x DRI) – – – – – – Unique for B vitamins Damage to nervous system Numbness and weakness Depression, fatigue HA Does not treat PMS Vitamin B6 in Foods Meat, poultry and fish Shellfish Whole-grain breads and cereals Green leafy vegetables Legumes Fruits 6. Vitamin B 12 Roles – Maintains sheaths that surround and protect nerves – Works with folate to make red blood cells DRI – 2.4 ug Vitamin B 12 Deficiency WHAT Pernicious anemia Large, immature blood cells Paralysis of nerves and muscles; permanent Folic acid corrects anemia but not the nerve and muscle damage WHO Strict Vegans Intrinsic factor Elderly (atrophic gastritis) Vitamin B12 Sources Animal Foods – Meat, poultry and fish – Milk and dairy products – Cheese – Eggs Other – Fortified soy beverages – Fortified cereals – Supplements – B 12 injections 7. Vitamin C Roles – Production and maintenance of collagen (connective tissue in bones, teeth, skin and tendons) – Wound healing – Release of stress hormones – Antioxidant DRI – 75-90 mg (increase if smoke) Vitamin C (cont) Deficiency – Scurvy – Small cell anemia – Frequent infections – Bleeding gums and loose teeth – Poor wound healing – Rough skin Toxicity (10 x DRI) – Nausea, diarrhea – Abdominal cramps – Kidney stones – Headache – Fatigue ANTIOXIDANTS (Vit C, E & beta-carotene) Free radicals (unstable oxygen compounds) – Smoking – Sunlight – Chemical reactions in body – Environmental pollution Cause damage – Enzymes – Cell membrane – DNA – Oxidized LDLcholesterol Antioxidants – Donate O2 to make stable