Vitamins are organic compounds that help maintain normal body functions, such as reproduction, growth and cell repair. Our body cannot produce vitamins, so we need to obtain them from other sources. Most of the vitamins we need come from the food we eat, except for two: vitamin D, which the body acquires when exposed to sunlight, and vitamin K, which is made by the bacteria in our intestines.
In addition to their presence in natural foods, vitamins can also be manufactured synthetically. Vitamin supplements may be available in tablet, capsules, or liquid form. These include:
Vitamin A – affects the formation and maintenance of skin, mucus membranes, bones and teeth, vision, and reproduction. Vitamin A is found in milk, butter, cheese, egg yolk, liver, and fish-liver oil.
Vitamin B Complex – are fragile, water-soluble substances, several of which are particularly important to carbohydrate metabolism. It is composed by vitamin B1 (thiamine), vitamin B2 (riboflavin), vitamin B3 (niacin), vitamin B6 (pyridoxine), vitamin B12 (cobalamin), folic acid, pantothenic acid, and biotin.
Vitamin C (Ascorbic acid) – important in the formation and maintenance of collagen, the protein that supports many body structures and plays a major role in the formation of bones and teeth. Sources of vitamin C include citrus fruits, fresh strawberries, cantaloupe, pineapple, and guava. Good vegetable sources are broccoli, Brussels sprouts, tomatoes, spinach, kale, green peppers, cabbage, and turnips.
Vitamin D – necessary for normal bone formation and for retention of calcium and phosphorus in the body. Also called the sunshine vitamin, vitamin D is obtained from egg yolk, liver, tuna, and vitamin-D fortified milk.
Vitamin E – plays some role in forming red blood cells and muscle and other tissues and in preventing the oxidation of vitamin A and fats. It is found in vegetable oils, wheat germ, liver, and leafy green vegetables.
Vitamin K – necessary mainly for the coagulation of blood. The richest sources of vitamin K are alfalfa and fish livers, which are used in making concentrated preparations of this vitamin. Dietary sources include all leafy green vegetables, egg yolks, soybean oil, and liver.
Minerals
Minerals are small amounts of metallic elements that are vital for the healthy growth of teeth and bones. They also help in cellular activities such as enzyme action, muscle contraction, nerve reaction, and blood clotting. Mineral nutrients are classified as major elements (calcium, chlorine, magnesium, phosphorus, potassium, sodium, and sulfur) and trace elements (chromium, copper, fluoride, iodine, iron, selenium, and zinc).
