The Truth About Hair, Skin and Nails Supplements

There’s no shortage of products on the market that are claimed to thicken hair, remove wrinkles, and fix dry, brittle nails. Among these are a slew of dietary supplements, some topping $100. But can a pill restore your hair, skin, and nails?

Here's what the research shows:

What the Science Says

Hair, skin, and nail supplements commonly contain antioxidants such as vitamins A, C, and E, or Coenzyme Q10, as well as biotin, a B-­complex vitamin. The minerals manganese and selenium are often found in supplements marketed for healthy hair, along with fatty acids such as fish oil and flaxseed oil. Deficiencies of these nutrients, ­although uncommon, may cause a litany of hair—and, sometimes, skin and nail—changes. Over time, for instance, insufficient intake of vitamins A and E can cause rough, scaly skin patches.

A deficiency of biotin may cause eczema and hair loss. But for those with no clear deficiencies, experts say there's no good evidence that supplements can make a difference. “I’m not aware of any robust data suggesting that any supplements can treat natural, aging-related hair loss or nail damage, or give you healthier skin,” says Pieter Cohen, M.D., an assistant professor of medicine at Harvard Medical School and an expert on dietary supplements. Two 1990s studies did find that biotin supplements may help strengthen soft, easily breakable nails. But the studies were small and not rigorously conducted, and haven’t been replicated, Cohen says. “It’s nothing that would ever lead me to recommend it to any of my patients,” he adds.

What If You're Deficient?

Most people get enough of the nutrients mentioned above through diet, but in rare cases, a medical problem may cause a deficiency or affect your hair, nails, or skin. People who take antibiotics long-term or use antiseizure drugs, for instance, are more likely to be biotin-deficient. An over- or underactive thyroid may cause hair loss and dry strands. Iron-deficiency anemia can lead to brittle, oddly shaped nails. If you’re experiencing chronic hair, nail, and skin problems for no clear reason, talk with your doctor. “If nothing shows up after appropriate testing, because we don’t have a good blood test to detect biotin deficiency, it might be worthwhile to try a supplement for three months,” says Marvin M. Lipman, M.D., Consumer Reports’ chief medical adviser. “Since biotin supplements can interfere with thyroid testing, make your doctor aware.”

But remember that dietary supplements are not tightly regulated by the Food and Drug Administration and might contain substances not listed on the label or have much less or more of an ingredient than promised. For example, in 2008, one brand of multivitamin was found to have 200 times the labeled concentration of selenium—after it had caused hair loss and discolored, brittle nails in about 200 people across 10 states. If you choose to take supplements, can you ensure that they are safe? Some carry one of four seals that might have some merit (U.S. Pharmacopeia, NSF International, ConsumerLab.com, and UL). Here, more about what these seals really mean.