Vitamins Tagreed Osman 1

Vitamins Are a group of organic nutrients required in small quantit ies for a variety of biochemical functions, forproper meta bolism, to protect health, and for normal growth and acti vity of the body. Also for the prevention of a number of diseases. Most vitamins cannot be synthesized by the body. They must be supplied in the diet. Vitamins are usually classified as water soluble or fat soluble 2

Types of Vitamins:   Fat-Soluble Vitamins   Water- Soluble Vitamins: 3

Fat-Soluble Vitamins: Properties: 1. Fat soluble vitamins often have very specialized functions Necessary for the function or structural integrity of specific body tissues and membranes. Can be retained in the body, and are not leached out quickly. Apolar hydrophobic compounds that can only be absorbed efficiently when there is normal fat absorption. Unlike water soluble vitamins, an excess of a fat soluble vitamin can be just as harmful as a deficiency 4

Water-Soluble Vitamins: Properties: Water-Soluble Vitamins: Properties: Act as catalysts and enzyme cofactors in metabolic processes and energy transfer. Act as catalysts and enzyme cofactors in metabolic processes and energy transfer. Are not stored in the body (excreted fairly rapidly) and must be replaced each day. Are not stored in the body (excreted fairly rapidly) and must be replaced each day. These vitamins are easily destroyed or washed out during food storage and preparation (overcooking) These vitamins are easily destroyed or washed out during food storage and preparation (overcooking) Water soluble vitamins do not accumulate in the body, so regular supplies are necessary Water soluble vitamins do not accumulate in the body, so regular supplies are necessary 5

FAT – SOLUBLE VITAMINS 6

Vitamin A: Vitamin A is also known as retinol Vitamin A Sources: Commonly found in cod liver oil, green vegetables, fruit dairy products, eggs, and liver Carrots indirectly serve as a source of vitamin A since they contain b carotene which the body readily converts to vitamin A 7

8 Vitamin A Functions: Role in aiding in night vision. Retinol is oxidized to retinal, which combines with the protein opsin to form rhodopsin. Rhodopsin is the active agent which converts light signals to electrical impulses that the optic nerve transmits to the brain

Vitamin A Deficiencies: A deficiency in vitamin A results in night blindness. The most serious deficiency results in a condition known as Xeropthalmia, a severe form of conjunctivitius or blindness. Excess of Vitamin A: Carotenemia; Bleeding; Hepatosplenomegaly (rare) 9

2-Vitamin D (Calciferol) Sources: Dairy products, eggs, Fish liver oils. Synthesized by sunlight action on skin. Dairy products, eggs, Fish liver oils. Synthesized by sunlight action on skin. Unlike other vitamins, the body synthesizes vitamin D in the skin through the action of ultraviolet light on 7- dehydrochlosterol Unlike other vitamins, the body synthesizes vitamin D in the skin through the action of ultraviolet light on 7- dehydrochlosterol Vitamin D Functions: Vitamin D is an important regulator of calcium metabolism. Vitamin D is an important regulator of calcium metabolism. It is involved in the uptake of calcium and phosphate ions from food into the body. It is involved in the uptake of calcium and phosphate ions from food into the body. It is necessary for the proper formation of bone structures and teeth. It is necessary for the proper formation of bone structures and teeth. 10

Vitamin D Deficiencies: Rickets (children) Rickets (children) Osteomalacia (adults) Osteomalacia (adults) Excess of Vitamin D : Hypercalcemia leading to metastatic calcification and renal damage (rare). Hypercalcemia leading to metastatic calcification and renal damage (rare).

3- Vitamin K Function: Blood clotting, Required for synthesis of Prothrombin (II) and clotting factors VII, IX and X.Blood clotting, Required for synthesis of Prothrombin (II) and clotting factors VII, IX and X.Sources: Green leafy vegetables, liver; Naturally produced by bacteria in the intestine.Green leafy vegetables, liver; Naturally produced by bacteria in the intestine.Deficiencies: Hemorrhagic diseaseHemorrhagic disease 12

Water-Soluble Vitamins: 1- B12 (Cyanocobalamin) Food source: Red meats, Liver, eggs, dairy products and fish Red meats, Liver, eggs, dairy products and fishFunction: Nucleic acid production Nucleic acid production Deficincy: Deficincy: Megaloblastic anemia (Pernicious anemia);neuropathy. Megaloblastic anemia (Pernicious anemia);neuropathy. 13

Vitamin C Sources: Citrus fruits, green leafy vegetables, tomatoes Citrus fruits, green leafy vegetables, tomatoesFunction: Collagen formation in teeth, bone, and connective tissue of blood vessels Collagen formation in teeth, bone, and connective tissue of blood vessels May help in resisting infection May help in resisting infection Absorption of iron, calcium, folacin Absorption of iron, calcium, folacin Ascorbic acid is a great antioxidant Ascorbic acid is a great antioxidant Works with vitamin E as a free-radical scavenger. Works with vitamin E as a free-radical scavenger. 14

Vitamin C Deficiencies Deficincy: Scurvy (breakdown of skin, blood vessels, and teeth) Scurvy (breakdown of skin, blood vessels, and teeth) mpaired wound healing. mpaired wound healing. *Vitamin C deficiency- often results secondary to hyperparathyroidism *Vitamin C deficiency- often results secondary to hyperparathyroidismExcess: None known, minimal-possibly urinary calculi, gastrointestinal complaints including diarrhea, nausea and abdominal cramps None known, minimal-possibly urinary calculi, gastrointestinal complaints including diarrhea, nausea and abdominal cramps 15

Folic Acid (Folacin) Source: Whole-wheat foods, green vegetables, legumes, organ meats, fish, citrus fruits. Whole-wheat foods, green vegetables, legumes, organ meats, fish, citrus fruits.Function: Nucleic acid metabolism Nucleic acid metabolismDeficiency: Megaloblastic anemia (Pernicious anemia) Megaloblastic anemia (Pernicious anemia)Excess: None None 16

Other vitamins: 1.Vitamin P (bioflavonoids, citrin): a.Helps increase strength of capillaries found in the mesocarp (tasteless, spongy, white layer beneath the rind) of lemon fruit. a.Helps increase strength of capillaries found in the mesocarp (tasteless, spongy, white layer beneath the rind) of lemon fruit. 2.Vitamin F (unsaturated fatty acids): a.Is important in respiration of vital organs. a.Is important in respiration of vital organs. i.-helps maintain resilience and lubrication of cells. i.-helps maintain resilience and lubrication of cells. ii.-helps regulate blood coagulation. ii.-helps regulate blood coagulation. iii.-is essential for normal glandular activity. iii.-is essential for normal glandular activity. 17

Other vitamins: 1.Vitamin B13 (Orotic acid): Is needed for the metabolism of some B-vitamins Is needed for the metabolism of some B-vitamins 2.Vitamin B15 (Pangamic acid): Helps eliminate hypoxia helps promote CHON metabolism stimulates nervous and glandular system Helps eliminate hypoxia helps promote CHON metabolism stimulates nervous and glandular system 3.Vitamin B17 (Laetrile): –has been linked to cancer prevention –has been linked to cancer prevention 18