Blind Faith in Vitamins
Vitamin supplements are taken by millions of people everyday despite almost no sound scientific evidence that they are safe or effective. Many studies have actually shown that they can be harmful. The most recent one shows that vitamin E supplementation in healthy middle-aged men greatly increases their prostate cancer risk.
The National Cancer Institute (NCI) sponsored a study that began in 2001 to evaluate the use of vitamin E, selenium and a combination of both against a placebo in the prevention of prostate cancer that stopped enrolling patients in 2008 when it demonstrated that after 1.5 years to 5 years of follow-up that neither vitamin E, selenium nor a combination of both supplements reduced prostate cancer risk, and that vitamin E was associated with a slight but statistically insignificant risk of developing prostate cancer when the preliminary data was analyzed after the participants had been followed for an average of 5.5 years. The latest data from the Selenium and Vitamin E Cancer Prevention Trial (SELECT) show that after 7 years of vitamin E supplementation, men in the trial had a 17% greater incidence of prostate cancer than those taking a placebo. This number did reach statistical significance. Since prostate cancer is the second leading cause of cancer and cancer death in men, 17% is a big deal. It means that for every 1000 men taking vitamin E, 11 of them will develop cancer who would not have otherwise.
Other studies have shown increased risk of strokes with high levels of vitamin E and increased risk of lung cancer in smokers taking vitamin A. Most of the handful of studies that have shown marginal and often statistically insignificant (likely not due to the vitamins) reductions in cancer incidence were conducted in countries like China where the populations studied had marginal deficiencies in the nutrients being studied.
When I tell patients that if they are eating a reasonably healthy diet, there is no need for, and possible harm can be caused by taking even a multi-vitamin regularly, I feel confident that my advice is supported by strong evidence. In addition to the clinical trials that support this recommendation, there are numerous reports of vitamins being contaminated with impurities ranging from lead to arsenic. Further, it’s well known that many vitamins and minerals, when taken in large quantities are quite toxic. A single large dose of iron can be fatal.
The FDA does not regulate the manufacturing or purity of nutritional supplements. Legislation passed in 1994 actually gave the FDA less authority over supplement manufacturers than it has over food processing plants. The only time the FDA has authority to intervene is after supplements have been sold to the public and the FDA can prove them unsafe. Beyond prohibiting companies from claiming that a supplement cures or prevents specific diseases, the law does nothing to regulate anything else they want to say about their products. Basically companies can put whatever they want into supplements and say whatever want about them, but until people start getting sick or dying, and only after the FDA can prove it’s because of their products, the public is at risk. I think that most people would be shocked to learn about the lack of regulation the $30 billion a year industry enjoys, particularly since 69% of the population takes some form of supplements and 84% of Americans surveyed feel that nutritional supplements are safe and effective at improving health. The FDA’s role in the regulation of supplements is summarized on their website:
There are situations where taking supplements is important. In diagnosed cases of vitamin deficiency, supplementation is essential. Anemic women who lack iron, typically because of menstrual blood loss, absolutely need iron. True vitamin D deficiency is another scenario, although recently studies have demonstrated that the level of vitamin D that is needed for good health is much lower than previously thought, and that supplementation to levels that were previously thought to be necessary may actually cause harm.
People with osteoporosis and those at risk for the disease should take vitamin D and calcium supplementation. Women who are planning to become or may become pregnant should take folic acid to prevent birth defects. However only about 50% of women are aware that they should start folic acid before becoming pregnant and only 25% of women do so, and studies of women with osteoporosis have shown that only half take vitamin D and calcium regularly. Worse still, numerous studies have shown that people with chronic illnesses like diabetes and high blood pressure take medication regularly only 50-70% of the time.
I am constantly baffled by people who take a handful of vitamin pills manufactured in an unregulated plant, filled with ingredients that could have come from anywhere, and that have no proven benefit in preventing any disease, but think that somehow a pure drug that has not only been produced in a facility closely regulated by the FDA but has also been subjected to clinical trials involving thousands of patients to prove its safety and efficacy is bad for them, and that they can cure these problems more holistically. Vitamins may be naturally occurring molecules, but they are far from natural. Nowhere in nature can one find pure vitamin E growing on a plant. It has only been since the early 1900s that we have had the knowledge and technology to manufacture pure vitamins.
The United States is in the minority of countries that does not regulate these substances like pharmaceutical products. Just iron supplements alone are responsible for 3,000 toxic overdoses in children in the U.S. annually and 10 of these are fatal. Countries in South East Asia used to put anti-malarial drugs in table salt as a public health measure, which led to disastrous levels of drug-resistant malaria that are still a problem in that area. It makes one think about the potential risks of spraying vitamins onto children’s breakfast cereals, and nearly every one is. From the Kellogg’s website, this historical tidbit is proudly stated “Kellogg’s® Pep™, became the first cereal fortified with vitamins through the “spray” method.” Most countries consider the adulteration of food with highly active chemicals something important enough to public health and safety to be regulated. It doesn’t matter whether the chemical is a vitamin or an antibiotic.
I fully support diet and lifestyle modifications. Eating a diet with more vegetables, whole grains, and less animal products, exercising, reducing alcohol intake, and not smoking are incredibly valuable for health as well as prevention and treatment of disease, but they are often not enough. The reason why the average lifespan in the United States is no longer 49 years, as it was at the turn of the nineteenth century is not because of organic farming, vitamin supplements, or yoga. We have the opportunity to achieve a life span of 80 because of improvements in medications, surgery, vaccines, sanitation, and our knowledge of disease and health.