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Vitamin C, ascorbic acid, is the most talked about vitamin. Many spectacular claims are made for this vitamin but none has so far been substantiated. Most animals produce their own vitamin C from chemicals within their bodies, but humans must rely on food sources. Because the body's ability to store vitamin C is limited, regular intake is important. Vitamin C is vital to the formation of collagen, the connective tissue that holds cells together. This vitamin helps to maintain the blood vessels, to form the dentine of the teeth, to harden bones, to heal burns and wounds, and form hemoglobin. Vitamin C also helps to make key hormones, to protect other nutrients within the body, and to fight infections. A prolonged lack of vitamin C leads to scurvy. This disease is practically eliminated in the adult population of the United States, but is sometimes seen in infants six months to one year of age who have had no vitamin C because of their limited diet. True scurvy causes breakdown of blood vessels, muscles, teeth, gums, bone, and skin. A less severe shortage of vitamin C causes bleeding gums, a tendency to bruise easily, and pain in the joints, as well as reduced resistance to infection. To protect the body from scurvy, a minimum of 10 milligrams of vitamin C is needed daily. However, to maintain a desirable level of vitamin C in the body at all times, the RDA is set at 60 milligrams to include everyone. This amount is enough to allow the body to store a five-month supply of vitamin C as a reserve against those days and weeks when the intake of vitamin C may be low. Very high levels of vitamin C have been recommended for curing the common cold, for preventing cancer, and for various other purposes. A number of carefully controlled studies have shown that vitamin C supplements do not prevent viral colds and flu, although they may slightly lessen the severity of the symptoms. There is some evidence that stress such as infection may slightly increase your need for vitamin C. Many people "under stress" consume large doses of vitamin C "just to be safe." The body uses only the amount of the vitamin it needs, and must eliminate most of the rest through the kidneys, storing only a small percentage. Moderate increases in vitamin C intake are probably harmless, but experts warn against the hazards of large doses, 10 or more times the RDA. Studies relate vitamin C megadoses to problems in treating blood diseases, risk of termination of pregnancy, formation of bladder and kidney stones, destruction of B12 in pills and in the body, and loss of calcium from the blood. Large doses can create a dependency that causes deficiency symptoms if dosages are lowered. Pregnant women taking mega doses of vitamin C may give birth to infants who show symptoms of scurvy and whose vitamin C requirements are abnormally high. Everyone knows that citrus fruits are good sources of vitamin C. Strawberries, melons, papayas, and tomatoes are also high in vitamin C, along with broccoli, spinach and other leafy greens, sweet potatoes, raw cabbage, white potatoes, and raw green peppers. .It's among the least stable of all the vitamins, easily destroyed by light, air, and heat. | 
