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Pill Poppers: The Truth About Vitamins

Not sure which bottle to buy in the vitamin aisle? We’ve got the skinny on the supplements you should take—and the ones to avoid.

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“A lot of people take better care of their cars than their bodies,” says Nancy Clark, Boston-based sports nutritionist and author of Food Guide for New Runners: Getting It Right From The Start. Just like the gas that goes into your ride, the right fuel will not only help you reach your running performance goals, but allow you to live a longer, healthier life.

We all know a runner’s diet should be rich in the good stuff: fruits, vegetables, whole grains and lean proteins. But what about pills, gel caps, tablets and liquid vitamins? Some supplements are worth their weight in Olympic gold, some might earn a silver medal and still others should be disqualified because they’re downright dangerous. Here’s how to sniff out the right supplements to take your meal plan to the next level.

Take It

Multivitamin with Iron

Clark says that eating fresh fruits and vegetables is the best way to get your vitamins. “If you’re eating right you are unlikely to require supplements, but they can be taken for health insurance,” she explains. Female runners often need to cash in that insurance policy because we lose iron through our menstrual cycle. A multivitamin with iron is likely to fill in most of your nutrition gaps, but Clark advises visiting your doctor before buying a bottle.


Electrolytes are naturally occurring charged particles including sodium, potassium, magnesium and calcium. You don’t need to take four extra pills in the morning, but you do need to replenish these nutrients when you’re out on a long run. “If you run more than 75 to 90 minutes at a high intensity, your sweat and sodium losses add up,” says nutritionist Monique Ryan, RD, author of Sports Nutrition for Endurance Athletes. The easiest way to supplement on the go is a sports drink that delivers electrolytes while keeping you hydrated.


Think that cup of java pre-race puts you at risk for dehydration? Think again. “Caffeine in moderate amounts is not dehydrating,” says Ryan. In fact, downing a caffeinated beverage or a gel spiked with caffeine can keep you going during a tough run. “A modest dose an hour before a workout or during a race in the form of a gel can improve performance. It can also help focus and concentration,” says Ryan. She recommends 300mg of caffeine (the amount in one grande Starbucks cup) before or 100mg (total) throughout a run. But be sure to test how your body reacts to caffeine before race day, so it won’t turn your stomach (or you) into a jitterbug at the starting line.

Try It

Vitamins C and E

City slickers, take note: A Scottish study found that these vitamins could protect your lungs from damage—and boost performance—when you run in a polluted area. “If you went for a long run in a large city where there are pollution concerns, 500mg of vitamin C and 100g of vitamin E would be prudent,” says Ryan. But be careful about taking higher doses. Too much vitamin E, for instance, can actually increase oxidation and have the opposite effect, irritating your airways.

B Vitamins

If your diet is rich in kale, Swiss chard and spinach, you’re probably getting your fill of B vitamins. But if the only green you’ve seen recently was the iceberg lettuce on your burger, your performance will suffer. Researchers from Oregon State University found that athletes who are B-deficient may have a reduced ability to repair and build muscle. And female athletes have it even worse. “Women who are  deficient in the B vitamin folic acid face an increased risk of having a baby with a birth defect,” Clark says.

Co-Enyzme Q10

If you’re running to improve heart health, popping some Co-Enyzme Q10 might be worth your while. Some studies show that supplementing with this enzyme reduces the side effects of cholesterol medication, such as muscle pain. Other research has found it to prevent recurrence of a heart attack and help lower blood pressure.

Avoid It


This plant-based supplement has become popular with both dieters and athletes. But there’s no research that proves the stimulant improves performance. Worse, it can be bad for your bod. “People take too much, causing unsafe heart arrhythmias which can even cause death,” says Ryan. Try incorporating coffee runs into your training plan instead. “Caffeine works without the risk of overdosing,” says Ryan.


The darling of bodybuilders, creatine isn’t something most runners need. If you’re doing intense track workouts, building muscle might improve your times, says Clark. But there are better ways to boost performance through proper training and meal planning. “Creatine can cause water weight gain and, as a result, potentially have a negative effect on performance,” she adds.

**Professional Opinion: Supplements can be part of a healthy diet. But before you swallow a handful of pills and hope for the best, see a specialist. “A registered dietician can help you manage food, stress, weight loss and performance goals,” Clark says. Plus, a standard blood test will uncover whether you have any nutritional deficits that need to be addressed. To find a local sports dietitian, use the referral network at