Brief Notes on Vitamins

'Both vitamins and minerals are necessary to a well-balanced diet. As a matter of fact, vitamins control your body's utilization of minerals. In addition, each vitamin seems to have a specific role to play in normal body function. On the other hand, if the mineral supply is deficient, there is little benefit from the vitamins. Without vitamins, your body can still appropriate some minerals from the reserve in your system. On the other hand, vitamins are powerless without minerals. Thus it is essential that one receives the necessary amounts of both '. -Dr. John B. Lust.

Vitamins are organic chemical substances, widely distributed in natural foods (fruits and vegetables) that are essential to normal metabolic functions of human beings and lower animals. Only very small amounts are needed but lack of the necessary amount, however small, results in a vitamin deficiency disease (avitaminosis). Among the classical examples of such diseases are rickets, scurvy, beriberi and pellagra.

A Polish chemist, Casimir Funk, invented vitamin in 1911 while trying to extract from rice hulls a chemical substance that would cure beriberi. He thought that he had found an amine chemical vital to life. He had not, but his theory was correct; lack of certain chemical substances caused disease. 

Vitamins are distinguished as fat-soluble, notably A, D, E and K, and water-soluble most of the others. Some are heat-labile, destroyed by cooking notably vitamin C; most are heat-stable.

Taking vitamin pills is not necessary. A good mixed diet of common foods, including protective foods, supplies all the vitamins one needs. Vitamin pills without a good mixed diet will not increase pep and vigour or resistance to disease.

Vitamin supplements are necessary. They are needed when the dietary intake of vitamins is inadequate. This condition often appears in cases of chronic disease, after delivery, after surgical operation, and during pregnancy.

Vitamin needs differ with age and many other factors. Thus vitamin D is much more essential to infants and growing children than to adults. Rarely is only a single vitamin missing from the diet. Most vitamin deficiencies are multiple; therefore vitamin pills and other vitamin preparations prescribed for preventing or treating disease contain a balanced supply of many vitamins.
Vitamin A, once called 'anti-infective vitamin', helps to preserve the integrity of the skin and mucous membranes and other epithelial tissues, making them more conducive to growth of bone and tooth formation. Its deficiency may cause night-blindness, changes in the eye, general weakness, retarded growth, problems of respiratory tract, genito-urinary troubles, gastro­intestinal disorders, and nervous troubles. It is essential to the formation of 'visual purple' rods and cones in the retina of the eyes; its lack causes night­-blindness. Vitamin A is found in fish, liver, milk, egg-­yolk and in many green fruits and vegetables like garlic, lemon, musumbi, apple, onion, potato, carrot, beet, orange, radish, cucumber, grape, pineapple, parsnip, cauliflower, sweet potato, turnip, brinjal, and in dark green leafy vegetables.
Vitamin B-complex includes a large number of water soluble vitamins like thiamine, riboflavin, niacin, pyridoxine, biotin, pantothenic acid, inositol, folic acid and vitamin B-12. 
Thiamine is essential for utilization of carbohydrates and normal appetite and function of the

digestive tract. Its deficiency may cause abdominal pains, heart irregularities, muscle tenderness, emotional instability, constipation and irritability. Thiamine is not stored in the body as effectively as many other vitamins; and it is apt to be lacking in the adult diet. Thiamine is often given to restore or improve appetite. Best sources of thiamine are pork and brewer's yeast; it is also found in whole grain, dried peas and beans, liver and egg yolk. Raw fruits and vegetables are also good source of thiamine, especially beet roots, cucumber, brinjal, onion, pumpkin, carrots, spinach, grape, orange peel, and raisin.
Riboflavin is necessary for normal growth and for the integrity of skin tissues and mucous membranes. Lack of riboflavin may cause the lips to sore and show slight fissures at the corners, the tongue to be red and sore, the eyes to itch and be extremely sensitive to light. Milk is the best source of riboflavin; other good sources are liver, kidneys, lean meat and peanut.
Niacin, also called nicotinic acid, is the pellagra preventive vitamin. Lack of niacin induces the symptoms of pellagra, namely diarrhea, skin eruptions and mental depression. Other symptoms are loss of appetite, loss of weight, and a sore tongue. Good sources are brewer's yeast, liver, kidney, salmon, lean meat, poultry and eggs. Vegetarian diet is deficient in niacin.
Vitamin B-12 derived from liver appears to increase the formation of red blood cells and has specific usefulness in treating pernicious anemia. Vitamin B deficiency causes general lassitude, constant tiredness, loss of vitality, slow heart-beat, gastric disorders, beriberi, nervousness, and poor appetite. It is found in asparagus, avocado, beans, beet, cabbage, carrots, cauliflower, lettuce, radish, potatoes, tomato, apples, bananas, grapes, lemons, oranges, pineapple, onions, pumpkins, spinach, grapes, raisins etc.
Vitamin C or ascorbic acid is a delicate vitamin, not well stored in the body and easily destroyed by heat (cooking). It must be replenished daily. It supplies a kind of cementing substance that binds cells together in the blood vessels, teeth, bones and other tissues. Lack of it causes the capillary blood vessels to break rather easily causing bleeding gums, loosened teeth, toothache, gumache, sores in the mouth or tongue, physical weakness, headache, tender joints, scurvy, restlessness, indigestion. The best sources of vitamin C are cabbage, green peas, tomato, lemons, lime, orange, musumbi, beans, carrots, beets, lettuce, raw onions, garlic, apples, bananas, pine- apples, cauliflower, pumpkin, pears, papaya, marmelos, turnips etc.
Vitamin D is practically non-existent in fruits and vegetables. It is essentially available in sunlight and for this reason it is known as 'sunshine vitamin'. It is essential to the utilization of calcium and phosphorus, especially in the formation of bone and teeth. Infants and growing children particularly need this vitamin. Its deficiency causes rickets, poor teeth formation, poor bone formation, convulsions, pigeon breasts, curvature of the spine, retarded growth, constipation, lack of vigour and vitality etc. Adults have little need of vitamin D. When exposed to sunlight, the human body manufactures its own vitamin D. The ultraviolet rays of the sun turn sterols, fatty substances found in the human skin, into vitamin D. Exposure of milk to ultraviolet light produces vitamin D milk. Cod liver oil and other fish oils are excellent sources of vitamin D; so are liver, butter and egg-yolk.
Vitamin E is described as a group of oil-soluble alcohols. Its deficiency causes impotency, miscarriage, loss of hair, sexual frigidity, impaired mentality, sterility, abortion etc. It also develops black and white patches in the skin. Best sources of vitamin E are wheat-germ oil, cottonseed oil, egg-yolks, and beef­ liver. It is also found in spinach, watercress, lettuce, celery, parsley, turnip leaves, etc.
Vitamin K is necessary to stop internal bleeding (gastric ulcer). It may be given by injection. This vitamin is available in cabbage, kale, cauliflower, spinach, tomato and in dark green leafy vegetables.