A randomized, double-blind, placebo-controlled clinical trial found that tart cherry juice increased sleep duration by 84 minutes in adults suffering from chronic insomnia after just two weeks of consumption.
The study, published in the American Journal of Therapeutics, evaluated adults aged 50 and older who consumed 8 ounces of Montmorency tart cherry juice twice daily—once in the morning and again 1–2 hours before bedtime. Researchers objectively measured sleep using overnight polysomnography, the gold-standard method for evaluating sleep architecture and duration.
After 14 days, participants with insomnia slept an average of 1 hour and 24 minutes longer when consuming tart cherry juice than when consuming placebo (p = 0.0182). Improvements in self-reported habitual sleep efficiency were also observed, with no adverse events reported.
The investigators identified several potential biological mechanisms underlying these effects. Tart cherries contain procyanidin B2, a polyphenol demonstrated in laboratory experiments to inhibit indoleamine 2,3-dioxygenase (IDO), an enzyme responsible for degrading tryptophan through the kynurenine pathway. Blood measurements revealed a significant reduction in the kynurenine-to-tryptophan ratio, suggesting greater tryptophan availability for serotonin and melatonin synthesis.
They also observed significantly reduced prostaglandin E2 (PGE2), an inflammatory mediator potentially involved in sleep disturbances. Although tart cherries naturally contain melatonin, their effects on tryptophan metabolism and inflammatory signaling may be more important than melatonin content alone.
Importantly, this was a small pilot trial involving eight participants, and larger studies are needed to determine whether the magnitude of improvement is reproducible. Nevertheless, these findings suggest that tart cherry juice represents a promising, inexpensive nutritional intervention for improving sleep duration in individuals with insomnia.
Epidemiologist and Foundation Administrator, McCullough Foundation
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Make sure it is organic tart cherry juice. Regular cherries are on the Dirty Dozen list by the EWG.
It also helps kill arthritic inflammation