Ask The Experts: Which Supplements Do Runners Need?

Matt Fitzgerald explains which are most beneficial.

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Dear Matt,

Are there any nutritional supplements I should be taking as a runner?


Atlanta, Ga.



Sports nutritionists have searched high and low for a nutritional supplement that enhances endurance performance the way creatine enhances strength, but so far they’ve come up empty. Numerous supplements, including certain antioxidants and amino acids, have demonstrated some promise as performance enhancers in preliminary studies only to fail subsequent tests.

However, there are some supplements that I recommend to runners for health benefits that may translate into performance benefits in those who are deficient in the nutrients they provide. First, I recommend that all runners take a daily multivitamin and multimineral supplement to fill any micronutrient gaps left by their diet. Second, I recommend that all runners take an omega-3 essential fatty acid supplement. Omega-3 fats are critical for optimal cellular health, nervous system function, and inflammatory responses, and it’s very difficult to get enough of them from the foods we eat.

There are three additional supplements that runners should take if testing by a physician indicates a need for them: calcium, iron, and vitamin D. All runners, and especially women over 40, should have their bone mineral density checked periodically. If it’s on the low side, take supplemental calcium under your doctor’s supervision. For reasons that are not entirely clear, iron deficiency anemia is very common among runners, and particularly female runners. If you suffer from unexplained fatigue, have your iron level and red blood cell count checked and follow your doctor’s advice for iron supplementation if the results indicate a need.

Finally, there’s been a lot of attention paid recently to vitamin D deficiency, which can impact exercise performance. Get your vitamin D level checked and correct any deficiency by increasing your sun exposure, supplementing, or both.


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Check out Matt’s latest book, Racing Weight Quick Start Guide: A 4-Week Weight-Loss Plan for Endurance Athletes.