Millions of Americans per year use supplements such as melatonin and valerian as a nondrug way to help them sleep, but there’s little evidence that they are effective. According to the American Academy of Sleep medicine, there is not enough research to clearly demonstrate they work—more is needed. What’s worse, there are significant safety concerns associated with them.

Though some individual studies suggest that melatonin and valerian might be better than a placebo at helping people fall asleep or stay asleep, large reviews evaluating such studies found that the sleep-inducing benefits of the products are minimal at best. A 2013 analysis in the journal Plos One found that people who took melatonin fell asleep only an average 7 minutes faster and slept 8 minutes longer than those taking a placebo. But the risks involved with long-term use of the products have not been well-studied.

Risks Outweigh Benefits

For most people, the risks, according to Shelby F. Harris, Psy.D., director of the Behavioral Sleep Medicine Program at Montefiore Medical Center in New York City, far outweigh any small benefit. “Just because you can buy it without a prescription doesn’t mean these supplements are without any side effects,” Harris advises. She says she commonly sees patients complaining of dizziness, nausea, vivid dreaming, and sleepiness while taking melatonin. About 20 percent of melatonin users in a 2015 Consumer Reports survey reported next-day grogginess. Melatonin can undermine the effectiveness of blood pressure drugs and diabetes medications.

Furthermore, as supplements, these products are not closely regulated by the Food and Drug Administration, so there’s little assurance of the quality and purity of the products. For instance, a 2013 analysis of ingredients in 10 valerian products found wide variation in both the list of ingredients in those pills and the amount of the herb in each. More concerning: Two of the products were found to be contaminated with lead.

Some Help for the Jet-Lagged

Melatonin might, in fact, be useful for those with jet lag or those who do shift work. In an American Academy of Sleep Medicine analysis, the majority of studies suggested an improvement in jet-lag symptoms for people who took melatonin at bedtime starting on the evening of arrival compared with those who took a placebo. Studies have also suggested that melatonin may help reset the internal clock of shift workers, suppressing their brain’s production of melatonin, which regulates the sleep-wake cycle.

If you try sleep supplements, look for products with the “USP Verified” mark, which indicates that the products meet U.S. Pharmacopeial Convention standards for how much active ingredient the pills contain and that they are clear of harmful substances. Stick with low doses, too, especially if you’re trying melatonin for the first time. Research suggests that 1 to 3 milligrams is enough for most people, and as little as 0.1 to 0.3 milligrams may be effective.

Editor's Note: This article also appeared in the February 2017 issue of Consumer Reports magazine.

These materials were made possible by a grant from the state Attorney General Consumer and Prescriber Education Grant Program, which is funded by a multistate settlement of consumer fraud claims regarding the marketing of the prescription drug Neurontin (gabapentin).