The Truth about Supplements

A Harvard study says it will be another five years before any real information is available.

Vitamins don't replace foodTry getting your nutrients from food, not pills. Supplement illustration via Shutterstock

According to Harvard Health Publications, more than half of us take supplements to get the vitamins and minerals that we aren’t getting from food, like calcium, potassium, magnesium, and vitamins A, C, and D. In some cases, people also take supplements for an extra health boost or because they think taking these pills will prevent disease. But can you really get your nutrients straight from a pill? The straight answer is no. And even worse, all those vitamins and pills you are buying are not regulated by the FDA. So who knows what is really in that capsule?

You’ve heard about the benefits before. All of the magazines quote studies about how vitamin D can help prevent cancer, diabetes, depression, and even the common cold. We’re guilty of this, too. You’ve also heard that omega-3 fatty acids have been praised for preventing strokes and other cardiovascular ailments. And then there’s antioxidants, like vitamins C and E, and beta carotene, which we are told can ward off heart disease, cancer, and even Alzheimer’s disease.

But here’s the big problem with all of this supposedly amazing research: According to Harvard Health Publications, many of the supplement studies were observational, meaning they didn’t test a particular supplement against a placebo (inactive pill) in a controlled setting. Unfortunately, the results of more stringent controlled trials haven’t concluded with the same good news.

After rigorous testing, some supplements where health benefits were touted in observational studies turned out to be ineffective and risky. Vitamin E, for example, which initially was thought to have heart protection benefits, but was found to increase the risk for bleeding strokes. Folic acid and other B vitamins, once believed to prevent heart disease and strokes, were found to increase cancer risk in high doses.

Harvard Health Publications explains that:

“Often the enthusiasm for these vitamins and supplements outpaces the evidence. And when the rigorous evidence is available from randomized controlled trials, often the results are at odds with the findings of the observational studies,” explains Dr. JoAnn Manson, chief of preventive medicine at Brigham and Women’s Hospital, professor of medicine at Harvard Medical School, and principal investigator of a large randomized trial known as VITAL (Vitamin D and Omega-3 Trial).

Because observational studies may not fully control for dietary factors, exercise habits, and other variables, they can’t prove whether the treatment is responsible for the health benefits. “People who take supplements tend to be more health conscious, exercise more, eat healthier diets, and have a whole host of lifestyle factors that can be difficult to control for fully in the statistical models,” Dr. Manson says.

For many popular supplements like vitamin D and omega-3 fatty acids, results from randomized controlled trials should be available within the next five years. The good news is that there has been one recent randomized controlled study, and the results published in the Journal of the American Medical Association are promising. Men taking a daily multivitamin had a statistically significant reduction in the incidence of total cancer than those men who took a placebo.

But until more testing can be done, the best way to get the vitamins and nutrients we need is the old fashioned way: through food. Harvard Health agrees:

“Usually it is best to try to get these vitamins and minerals and nutrients from food as opposed to supplements,” Dr. Manson says.