Year proposed 1930s | ||
Claims Health effects from very high doses of vitamins. Related scientific disciplines Notable proponents Fred R. Klenner, Linus Pauling | ||
Megavitamin therapy is the use of large doses of vitamins, often many times greater than the recommended dietary allowance (RDA) in the attempt to prevent or treat diseases. Megavitamin therapy is typically used in alternative medicine by practitioners who call their approach "orthomolecular medicine", but also used in mainstream medicine for "exceedingly rare" genetic conditions that respond to megadoses of vitamins.
Contents
Nutrients may be useful in preventing and treating some illnesses, but the conclusions of medical research are that the broad claims of disease treatment by advocates of megavitamin therapy are unsubstantiated by the available evidence. It is generally accepted that doses of any vitamin greatly in excess of nutritional requirements, will result either in toxicity or in the excess simply being metabolised - evidence in favour of vitamin supplementation supports only doses in the normal range. Critics have described some aspects of orthomolecular medicine as food faddism or even quackery. Research on nutrient supplementation in general suggests that some nutritional supplements might be beneficial, and that others might be harmful; several specific nutritional therapies are associated with an increased likelihood of the condition they are meant to prevent.
Multivitamin vs megavitamin
Megavitamin therapy must be distinguished from the usual 'vitamin supplementation' approach of traditional multivitamin pills. Megavitamin doses are far higher than the levels of vitamins ordinarily available through western diets. Multivitamin supplementation has been demonstrated to have negligible effect in treating cancer.
A study of 161,000 individuals (post-menopausal women) provided, in the words of the authors, "convincing evidence that multivitamin use has little or no influence on the risk of common cancers, cardiovascular disease, or total mortality in postmenopausal women".
History
In the 1930s and 1940s, some scientific and clinical evidence suggested that there might be beneficial uses of vitamins C, E, and B3 in large doses. Beginning in the 1930s, the Shutes in Canada developed a megadose vitamin E therapy for cardiovascular and circulatory complaints, naming it the "Shute protocol".
Tentative experiments in the 1930s with larger doses of vitamin C were superseded by Fred R. Klenner's development of megadose intravenous vitamin C treatments for polio and other viruses in the 1940s. William Kaufman published articles in the 1940s that detailed his treatment of arthritis with frequent, high doses of niacinamide.
In 1954, Rudolf Altschul and Abram Hoffer applied large doses of the immediate release form of niacin (Vitamin B3) to treat hypercholesterolemia. In a 1956 publication entitled Biochemical Individuality, Roger J. Williams introduced concepts for individualized megavitamins and nutrients. Megavitamin therapies were also publicly advocated by Linus Pauling in the late 1960s. In 1956, experimental results suggested niacin could be useful in the treatment of high cholesterol, results that were confirmed in 1986.
Usage of therapy
An American cottage industry in the late 20th century, evolving megavitamin therapies are integrated with orthomolecular and naturopathic medicine.
Although megavitamin therapies still largely remain outside of the structure of evidence-based medicine, they are increasingly used by patients, with or without the approval of their treating physicians.
In 2008, researchers established that higher vitamin C intake reduces serum uric acid levels and may be useful in the prevention of gout.
The proposed efficacy of various megavitamin therapies to reduce cancer risk has been contradicted by results of one clinical trial. A review of clinical trials in the treatment of colds with small and large doses of Vitamin C has established that there is no evidence that it decreases the incidence of common colds. After 33 years of research, it is still not established whether vitamin C can be used as a treatment for cancer.
While some vitamins have no known tolerable upper intake level, others, including vitamins A and D, are known to be toxic at high doses. All vitamins known to be toxic in high doses are fat-soluble, not water-soluble, as water-soluble vitamins can be voided via urine within a reasonable timeframe.
Because vitamin intake can alter metabolism as much as medications, short term vacations from any single or multivitamin intake are generally recommended (by the medical and homeopathic communities) so as to allow the body to use up excess vitamin reserves and stabilize its internal chemistry.
Controversy
Although Linus Pauling is known for highly respectable research in chemistry and biochemistry, he is also known for promoting the consumption of vitamin C in large doses. Pauling wrote multiple books endorsing vitamin C megadosing. Although he claimed and stood firm in his claim that consuming over 1,000 mg is helpful for one’s immune system when fighting a head cold, the results of empirical research do not align with this view. Researchers Vitetta, Sali, Paspaliaris, and Reavley (2002) completed a double blind randomized control study with 400 healthy participants. Throughout the 18 month experiment, there were 189 reported cases of head colds. Researchers found that there were no significant differences between the medication groups, and taking 1,000 mg of vitamin C at the first signs of a head cold did not help (Vitetta et al., 2002). There are also some minor yet unwanted ailments associated with vitamin C megadosing. These ailments were first noted in 1981 by Dr. Fong, who said that large doses of vitamin C can cause diarrhea and urethritis for limited amounts of time (Fong, 1981).
Despite some research supporting vitamin megadosing for certain conditions, research has also revealed that in high levels, fat soluble vitamins (i.e., vitamin A, D, E, and K) can be toxic. A study by Bothra, Gupta, and Jain (2016) found that a large dose of vitamin D helped children with nutritional rickets; however, they noted concerns about vitamin D toxicity. Specifically, 1.5 months after the injection, some children had toxic levels of vitamin D (Bothra et al., 2016).
Since megavitamin therapy/ vitamin megadosing is considered alternative medicine and it is endorsed by homeopathic communities, it is important to make cautious decisions regarding vitamin intake as homeopathy has been proven ineffective by scientific researchers. Additionally, it is important to note that water-soluble vitamins, in excess, are excreted through urine, while fat-soluble vitamins, in large doses, can lead to toxicity. It is essential to consult a medical practitioner before attempting any megavitamin therapy as medical practitioners can verify up-to-date research on efficacy and safety.