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  • More people are taking melatonin supplements to help with sleep, according to new research.
  • Melatonin is a hormone that is naturally produced in the body, but it can also be consumed in supplement form.
  • Past studies have found that labels on melatonin supplements were inaccurate.

More people are taking supplemental melatonin, and at increasingly high doses, according to a research letter recently published in the Journal of the American Medical Association (JAMA).

Researchers point out these findings raise safety concerns since the actual dose of melatonin supplements could be nearly 500 percent higher than the label indicates.

For this study, researchers analyzed roughly 20 years of data from the National Health and Nutrition Examination Survey to examine reported prevalence and trends in use of supplemental melatonin among over 55,000 U.S. adults.

They also wanted to determine the prevalence of people using more than 5 milligrams (mg) of the sleep aid per day.

The findings show that by 2018, people were taking over twice the amount of melatonin than they did 10 years before.

“Given the increasing popularity in use of exogenous melatonin, our observations support the need for better awareness of safety and effects of melatonin supplements in the public as well as among medical professionals,” said Naima Covassin, PhD, a senior research fellow in the department of cardiovascular medicine at Mayo Clinic in Rochester, Minnesota, and one of the study authors.

She added that little is known about how melatonin interacts with other drugs and whether chronic use is safe.

“While melatonin supplements are generally considered safe and well tolerated, side effects have been reported, especially at high doses and in patients with preexisting health risk factors,” said Covassin.

She emphasized that the increasing popularity of supplemental melatonin supports the need for better awareness of the safety and effects of melatonin supplements among the public and medical professionals.

“The results of increased melatonin consumption from 1999 to 2000 through 2017 to 2018 were not surprising,” Covassin said. “However, we were surprised by finding an increase in use of high dose melatonin (over 5 mg per day), which has become apparent over recent years.”

Melatonin is a hormone the body produces.

“Your body naturally produces melatonin in your pineal gland, and it is an essential hormone for helping to regulate your circadian rhythm,” Dr. Stacie J. Stephenson, also known as the “VibrantDoc,” a recognized leader in functional medicine and author of the self-care book “Vibrant: A Groundbreaking Program to Get Energized, Reverse Aging, and Glow,” told Healthline.

She explained that the pineal gland takes its cues from light, and it can get “confused” with light exposure at night or darkness during the day.

“You may consequently have trouble getting to sleep or staying asleep,” said Stephenson. “The occasional use of supplemental melatonin can help to regulate circadian rhythm by giving your body what your pineal gland may not be producing sufficiently.”

While melatonin supplements can help people get a good night’s sleep, past research finds that supplement labels may be inaccurate. The Food and Drug Administration (FDA) does not regulate supplements like it does for drugs.

Stephenson said a 2017 study evaluating melatonin content in dietary supplements showed over 70 percent of melatonin supplements didn’t contain the dose stated on the label.

“[The] actual content was up to 83 percent less than stated or up to 478 percent more than stated,” she said.

According to Stephenson, the study also found that even within different bottles of the same supplement line, there was as much as 465 percent variability of ingredients.

“Furthermore, the study showed that some brands also included significant amounts of serotonin (a neurotransmitter), which was not claimed on the label — and that could be hazardous,” she said.

“Adulterated supplements are actually quite common. I would certainly be cautious and look for quality control data on any supplement you choose,” Stephenson added.

“Melatonin is considered a dietary supplement and is not FDA approved for safety or effectiveness,” confirmed Sarah Gallucci, DO, an assistant professor of medicine in the department of sleep medicine at the University of Cincinnati College of Medicine.

She added that there is an organization that confirms the claimed dosage and purity of some brands.

“Supplements that are verified by the United States Pharmacopeial convention are the most reliable,” said Gallucci. “USP verified supplements are tested to ensure that the potency and amounts match the label and that the product does not contain harmful levels of specified contaminants.”

Gallucci added that melatonin is considered “generally safe,” with few serious adverse effects.

“The most common side effects are headache, dizziness, nausea, and fatigue,” she said.

Gallucci cautioned that taking too much melatonin could disrupt our sleep-wake cycle, making it more difficult to fall asleep.

“Safe starting doses range from 2 to 5 mg,” she advised. “Melatonin does not have any addictive potential, which can be seen with some prescription sleep medications.”

New research finds that people are using increasing amounts of supplemental melatonin, which is raising safety concerns.

Experts say that overdosing on melatonin can disrupt a person’s sleep cycle and cause side effects like headaches and nausea.

They also say that some brands have inaccurate doing labels and could contain potentially harmful contaminants.