Treatment of diseases with very high doses of vitamins, many times the reference intakes; little or no evidence for its efficacy; vitamins A, D and B6 are known to be toxic at high levels of intake.
Treatment of a disease with large dosages of vitamins. The consumption or administration of vitamins in dosages exceeding the RDAs by a factor of 10 or more.
Theory that the intake of very large doses of vitamins much above recommended daily doses will prevent or cure many physical and psychological disorders.
Practice of taking large concentrated doses of vitamins to prevent disease. Megavitamin therapy was a side development of the rash of newly discovered vitamins that took place during the 1930s. Scientists had recognized the importance of diet in a healthy life for centuries. Scottish physician James Lind showed during the 1750s that sailors could reduce their risk of contracting scurvy (caused by a lack of vitamin C in their diet) by drinking lime juice. The term “vitamin” itself, however, was not developed until 1912, when Polish chemist Casimir Funk isolated vitamin B2, or thiamine. In 1937, scientists in the southern United States were investigating outbreaks of pellagra, a disease caused by a deficiency of a vitamin called niacin. Pellagra victims suffered from some physical symptoms reddened skins, sore mouths but they also showed signs of mental disorders, including confusion and depression. These scientists discovered that when their patients were treated with niacin, their mental problems disappeared along with their physical symptoms.
In the 1950s, scientists began to treat mental problems specifically with niacin. Two Canadian doctors, Abram Hoffer and Humphrey Osmond, tried a niacin-based therapy on schizophrenic patients. Their results, published in 1962, showed that administering large, controlled doses of niacin had relieved some of the symptoms of the patients’ schizophrenia. Popular medicine picked up on this “megavitamin” approach and introduced it to the public. People began to believe that many physical diseases, as well as mental disorders, could be prevented through large doses of vitamins. Large amounts of vita¬ min Bi it was thought, could prevent mosquito bites. Some scientists, including Dr. Linus Pauling, advanced the theory that the common cold could be prevented through megadoses of vitamin C. As a result of this kind of thinking, nearly half the population of the United States takes some form of vitamin supplement each day to ward off disease.