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Vitamins and Supplements for Athletes? Only in Special Cases

Bert R. Mandelbaum, MD, DHL (Hon)


October 21, 2015

Nothing Replaces a Balanced Diet

One point I make in these conversations is that vitamins are extraneous for most people who eat a balanced diet. A good example is eicosapentaenoic acid (EPA), an omega-3 fatty acid. In the late 1970s, researchers studied Inuit who were eating only fish and had little incidence of cardiac disease.[8]

Some people extrapolated from this finding that folks in the United States who were eating Big Macs could avoid heart disease by swallowing fish oil supplements without changing their diet. Forty years later, no one has proved this.[8] The story of vitamin E is similar.[9] Over and over, we have isolated one molecule from a healthy diet of whole foods and expected it to work miracles. And over and over, we've been disappointed.

Some athletes hope that their supplements can compensate for the unhealthy foods they eat. But in the case of antioxidants, that doesn't seem to work. Researchers have measured free radicals and watched the levels shoot up when their subjects drank a pint of vodka. With antioxidants, you can deflect that a little, but the effect is not robust enough to counteract the negative effects.[10]

What is a balanced diet? The American College of Sports Medicine and the Academy of Nutrition and Dietetics guidelines are helpful. For those who want more specific recommendations, I always say that the Mediterranean diet is by far the best way to go. It features fish, fruits, nuts, and vegetables and not much beef and animal fat. And it's been shown in prospective trials to extend life.[11]

I recommend adding or subtracting carbohydrates, proteins, and fats based on which of these macronutrients an individual needs. The needs of the couch potato are very different from those of the triathlete. And the needs of the 16-year-old on a high school track team are different from those of a 70-year-old master runner.

A Few Exceptions

However, there are specific situations where I do recommend supplements. For example, when athletes are exercising so hard that they lose a lot of electrolytes, it may be hard for them to compensate for these deficits with diet alone, especially in very hot and humid climates.[12] In these cases, I think it's a good thing to take multivitamins and particularly magnesium, calcium, and zinc.

A growing number of people are vitamin-D deficient, and this has been associated with stress injuries and even cancer. I also sometimes recommend vitamin D, calcium, and sometimes iron for competitive female athletes. As athletic women grow older, their need for calcium goes up, especially when their hormones are naturally cycling down.[13]

Athletes who truly need supplements should look for products that are independently certified to contain the ingredients listed on the label and not contaminants or substances banned for athletic competition. One organization that provides such certification is NSF International, through its Certified for Sport program.[14]

Amateur athletes don't have to contend with drug tests. They're in a position to consider some substances that, from a therapeutic perspective, are normally off-limits to the professional or elite athlete. For example, male master athletes may want to consider testosterone supplements if they are coping with androgen deficiency, which can reduce their muscle mass and strength.[15]

Female master athletes may benefit from estrogen replacement because they run an increased risk for injury to the joints with reduced estrogen levels.[16] Each of these judgments and decisions should always be made in concert with a physician, as there are significant risks, as well potential benefits, in both cases. Take the initiative. Broach this subject with your patients who are athletic.

Risky Even When Indicated

Recently we have observed that testosterone supplementation can increase the risk for thrombosis.[15] Estrogen replacement can increase the risk for breast cancer and heart disease.[16] If athletes are truly deficient in a hormone, then discuss the pros and cons of supplementation with them before writing a prescription.

None of this is exciting or dramatic. In fact, it pretty much boils down to moderation and common sense. But as sports medicine professionals, that's sometimes all we have to sell.


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