vitamins and supplements

Vitamins & supplements

Which supplements are worth taking? (Hint: Not many.) Which are a waste, or can even be harmful? We look at the evidence for some popular supplements and conditions.

confused woman biting lip

Should you take a multivitamin?

Do you need a multivitamin? The short answer: We don’t know. But here's why taking a multi may make sense.

What to consider
multivitamin label

Vitamins and minerals, explained

How much of each vitamin and mineral do you need from foods and supplements combined? How much is too much?

See our guide

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Buyer beware

Hoping to keep your brain sharp? Boost energy? Improve your mood? There’s a supplement for that…if you believe marketers. But many supplements don’t live up to their claims. And some—especially risky weight loss, sexual enhancement, or bodybuilding supplements—may even contain undisclosed illegal, dangerous drugs.

Vitamin D

It’s tough to reach the recommended intake for vitamin D from food. Your body can make vitamin D from sunlight, but not if you’re wearing sunscreen (you should). That’s why many people need a supplement to help protect their bones. Here’s what vitamin D can—and can’t—do.

Drug interactions

Featured content for NutritionAction subscribers
a bottle of st. john's wort

Supplements

How some supplements interfere with medications

It’s not only certain foods that can spell trouble for some medications. One of the worst offenders: St. John’s wort. A phytochemical in the herb ramps up the cytochrome P450 3A4 (CYP3A4) enzyme. (That’s the opposite of what grapefruit does to the enzyme.) That spurs the breakdown of many drugs.