Vitamins
Vitamins are organic compounds required by organisms as vital nutrients in limited amounts. Vitamins are therefore essential to a balanced diet. Vitamins have a variety of functions in the body. Some vitamins are coenzymes, which means that they help enzymes to catalyse a reaction efficiently. Some are responsible for regulating metabolism or act as regulators of cell and tissue growth and differentiation.
Vitamin | Role | Food sources | Deficiency disease |
| Vitamin A | Needed for proper functioning of eyes | liver, carrots, egg | night blindness |
| Vitamin B (A group of vitamins with related functions) | Carbohydrate, protein, lipid, nucleic acid and alcohol metabolism; neurotransmitter synthesis and nerve function; red blood cell production | grains, potatoes, bananas | B1- beriberi, B3- pellagra, B6, B9, B12- anaemia |
| Vitamin C | Combines with key enzymes in metabolic reactions | citrus fruit (oranges, lemons etc) | scurvy (results in bleeding gums) |
| Vitamin D | Metabolites important in absorption of minerals from the gut (such as calcium and phosphate) | sunshine | rickets (resulting in soft bones, with bowed legs and widened wrists) |
| Vitamin E | Acts as an anti-oxidant | margarine, soybean oil, fortified cereals, condensed cow’s milk, cheese, orange juice | depressed immune system, anaemia, poor nerve conduction |
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