The U.S. women’s national soccer team uses many products for exercise recovery and sleep. Some are high-tech and expensive — red light therapy, and hyperbaric and cryotherapy chambers. One, though, is simple — tart cherry juice.

The players drink it to “enhance sleep and promote good sleep quality,” said Ellie Maybury, the team’s head of performance. It also helps them “from a muscle recovery standpoint, those anti-inflammatory properties that kind of help their muscles recover,” she said.

Several studies have shown that tart cherry juice can help reduce muscle soreness and improve sleep quality, and some sports scientists such as Maybury recommend it for their athletes. A USWNT spokesperson declined to identify the brands that players drink, but midfielder Lindsey Horan is an investor in Cheribundi, a tart cherry juice manufacturer.

Videos on the “benefits of tart cherry juice” on TikTok have amassed over 10 million views, and many of the users echo similar endorsements.

Not all scientists are convinced, though. They believe the data, while promising, is not clear. Most of the studies showing positive results have been small and not always independent, with some funded by the cherry industry.

Drinking tart cherry juice can have antioxidant or anti-inflammatory effects, experts say.

A systematic review and meta-analysis published in the International Journal of Sport Nutrition and Exercise Metabolism in 2021 looked at 14 studies and concluded that tart cherry juice can “aid the recovery of muscle function and attenuate soreness following strenuous exercise.” The cherry juice was typically taken several days before, the day of and a few days after the exercise protocol.

All the juice studied came from Montmorency cherries grown predominantly in Michigan, according to Malachy McHugh, an exercise physiologist who wrote a recent review on the role of cherry juice in exercise recovery. McHugh, the director of research at the Nicholas Institute of Sports Medicine and Athletic Trauma at Lenox Hill Hospital in New York City, said he was a consultant for Cheribundi (formerly CherryPharm) from 2006 to 2018 but waited until he no longer had a relationship with the company to write the review.

A 2009 study published in the Scandinavian Journal of Medicine and Science in Sports observed 20 recreational runners who were assigned to either tart cherry juice or a placebo for five days before, the day of and for 48 hours after a marathon run. The researchers, which included McHugh, found that isometric strength recovered faster in the cherry juice group, and the total antioxidant status for those runners was greater, as well.

I had a big pain in the neck. Then I ate a bunch of tart cherries.

The reduction in inflammation and oxidative stress from drinking tart cherry juice can allow athletes competing at a high level in multiday tournaments such as the World Cup to recover faster, said Kenneth Vitale, a sports medicine physician in orthopedic surgery at the University of California at San Diego.

“If you’re already at your peak, and your goal is mainly to reduce pain, inflammation and oxidative stress, and get a faster recovery back to your baseline, this may be of benefit,” he said.

Vitale cautioned, however, that recreational athletes may not need that exogenous dose of antioxidants or anti-inflammatory product, because they may inhibit the body’s natural adaptation response.

“You want to encourage a little bit of inflammation and a little bit of oxidative stress,” he said. “That’s the whole point of going to the gym and slowly increasing your distance or weight. Cherry juice, if you take too much of it, can inhibit that very stress because it’s an antioxidant, anti-inflammatory.”

Some researchers, though, believe that these study sizes are too small to provide any scientific validation of tart cherry juice’s benefits.

“None of these studies are large enough to be able to convince all doctors to start recommending it after vigorous exercise,” said Pieter Cohen, an internist at Cambridge Health Alliance and associate professor at Harvard Medical School. “But there’s preliminary, provocative information that suggests there might be something in these Montmorency cherries.”

There is some evidence that tart cherry juice contains sufficient melatonin to affect sleep quality.

In our bodies, melatonin is produced in our brains and acts as a hormone to help control circadian rhythms and sleep, said Louise Burke, the chair of sports nutrition at the Mary MacKillop Institute for Health Research at the Australian Catholic University.

One study published in the European Journal of Nutrition in 2011 had 20 volunteers consume either a tart cherry juice concentrate or a placebo for seven days. The researchers, including McHugh, found that the total melatonin content was significantly elevated in the cherry juice group.

Burke, who was not involved in the study, called it “solid and trustworthy,” but added in an email that “we need more confirmation that melatonin levels are reliable across all cherry supplements/fruit forms and whether this is always useful.”

Researchers in another study published last year in the International Journal of Environmental Research and Public Health studied 19 elite female field hockey players and found that tart cherry juice intake could not change melatonin and cortisol levels but could improve the players’ sleep quality.

The results, Cohen said, are not statistically significant because of the small number of study participants. “I would not expect that sour cherries will help with sleep given the current evidence available,” he said.

Even with the mixed messages, some coaches and exercise scientists believe in the power of tart cherry juice.

Sue Saunders, a registered dietitian for Monumental Sports, the ownership group that oversees the Washington Wizards, Mystics, Capitals and Capital City Go-Go professional sports teams, said that drinking 8 to 12 ounces of tart cherry juice is a daily ritual for many of the teams’ athletes.

“We consider it essential to recovery,” Saunders said, adding that Monumental Sports does not have any partnerships with cherry juice companies, and the organization purchases the drinks for its athletes.

Experts may not agree on the potential benefits of tart cherry juice, but many say it can be worth a try.

“I don’t think there are any major adverse effects,” said Glenn Wadley, a professor of exercise metabolism at Deakin University in Victoria, Australia. “There’s no evidence it impairs performance or impairs recovery.”

Some users who are not used to the taste may experience a gastrointestinal effect or distress. “Some people, it just goes right through them,” Vitale said. “It’s not harmful, per se. It’s just a bothersome side effect.”

To help with the taste, Monumental Sports athletes will add water or mix the juice in a smoothie, Saunders said. “Tart cherry is definitely an acquired taste,” she said. “It’s not the same as having a glass of apple juice.”

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