This document provides an overview of vitamins, including their categories, food sources, and functions. It discusses water soluble vitamins like thiamine, riboflavin, niacin, pyridoxine, folate, cobalamin, biotin, pantothenic acid, and choline. It also covers fat soluble vitamins A, D, E, and K. For each vitamin, it lists its functions, recommended daily intake, and deficiency symptoms.

1. VITAMINS BIOCHEM LEC WK 5

2. VITAMINS VITAMINS- essential organic molecules needed in very small amounts for cellular metabolism Primary Deficiency of a Vitamin- occurs when the vitamin is not consumed in sufficient amounts to meet physiologic needs Secondary Deficiency- develops when absorption is impaired or excess excretion occurs

3. VITAMINS Categories Water Soluble Vitamins- Vitamin B Complex, Choline, Vitamin C Fat Soluble Vitamins- Vitamins A, D, E, K Food Sources: Almost all foods, yet NO one food group is a good source of all vitamins; fresh fruits and vegetables are particularly rich sources

4. WATER SOLUBLE VITAMINS THIAMINE (B1) functions: to serve as coenzyme in energy metabolism; role in nerve functioning related to muscle actions RDA: 1.2 mg for men/ 1.1 mg for women Deficiency: BERI-BERI—2 Types WET- manifests with edema affecting cardiac function DRY- affects the CNS, producing paralysis and extreme muscle wasting Toxicity: non-toxic; excess is excreted in urine

5. WATER SOLUBLE VITAMINS RIBOFLAVIN (B2) function: coenzyme in the release of energy from nutrients sensitive to light RDA: 1.3 mg for men/ 1.1 mg for women Deficiency: ARIBOFLAVINOSIS—S/SX CHEILOSIS- lips become swollen and cracks develop in corners of the mouth GLOSSITIS- inflammation of the tongue

6. WATER SOLUBLE VITAMINS NIACIN (B3) functions: coenzyme for many enzymes; critical for glycolysis and Kreb’s cycle occurs naturally in 2 forms: NICOTINIC ACID and NIACINAMIDE RDA: 16 NE for men/ 14 NE for women Deficiency: PELLAGRA—3D’s ( Diarrhea, Dermatitis, Dementia )

7. WATER SOLUBLE VITAMINS PYRIDOXINE (B6) functions: coenzyme in the metabolism of amino acids and CHON 3 forms ( pyridoxine, pyridoxal, pyridoxamine ) all can be converted to the coenzyme pyridoxal phosphate for use in the body RDA: 1.3 mg for men and women Deficiency: S/SX: dermatitis, altered nerve function, weakness

8. WATER SOLUBLE VITAMINS FOLATE function: coenzyme in reactions involving the transfer of 1-Carbon units during metabolism 4 forms ( folate, folic acid, folacin and pteroylglutamic acid ) for folate to be maintained for use in the body, Vitamin B12 must be available folate has a role in proper formation of fetal neural tubes (brain and spinal cord development) RDA: 400 mcg for men/women 600mcg for pregnant women Deficiency: megaloblastic anemia—large RBC that cannot carry oxygen

9. WATER SOLUBLE VITAMINS COBALAMIN/CYANOCOBALAMIN (B12) functions: coenzyme in nucleic acid metabolism; needed for maturation of RBC absorption of Vitamin B12 relies on an intrinsic factor (IF) a substance produced by stomach mucosa deficiency: Pernicious Anemia- inadequate RBC formation caused by lack of IF in the stomach

10. WATER SOLUBLE VITAMINS BIOTIN function: coenzyme in synthesis of fat, glycogen and amino acids deficiency: S/SX: scaly red skin rash, hair loss, loss of appetite, depression

11. WATER SOLUBLE VITAMINS PANTOTHENIC ACID function: for metabolism of CHO, FATS and CHON deficiency: do not occur in nature CHOLINE function: needed for synthesis of acetylcholine, a neurotransmitter, and lecithin( phospholipid) deficiency: rare

12. WATER SOLUBLE VITAMINS ASCORBIC ACID ( VITAMIN C ) functions: collagen synthesis and other CT; antioxidant; iron absorption; coenzyme RDA: 90 mg for men/ 75 for women/ 125 mg for smokers Deficiency: SCURVY: S/SX—inflammation of CT, gingivitis, muscle degeneration, bruising and hemorrhaging as the vascular system weakens

13. FAT SOLUBLE VITAMINS VITAMIN A functions: component of visual pigments; needed for maintenance of epithelial tissues; antioxidant RDA: 900 mcg RAE for men/ 700 mcg RAE for women Deficiency: XEROPHTHALMIA—night blindness progressing to a hard, dry cornea (keratinization) resulting in complete blindness

14. FAT SOLUBLE VITAMINS VITAMIN D function: aid in absorption and use of calcium and phosphorus; promotes bone growth precursor: 7-dehydrocholesterol (found in the skin) active form: 1,25- dihydrocholecalciferol deficiency: RICKETS- a childhood disorder caused by Vitamin D or Calcium deficiency that leads to insufficient mineralization of bone and tooth matrix

15. FAT SOLUBLE VITAMINS VITAMIN E (TOCOPHEROLS) function: antioxidant RDA: 15 mg TE for men/women Deficiency: rare VITAMIN K function: cofactor in the synthesis of blood clotting factors deficiency: inhibits blood coagulation