Benefits
Blood pressure readings with a daily sweet cherry drink
In a single-blind trial in adults with obesity, a dark sweet cherry concentrate and powder drink taken twice a day for 30 days ended with systolic pressure lower than on a placebo drink, but the cherry group had also started lower, and diastolic pressure fell more on cherry from a lower starting point. Blood pressure was not a registered outcome, 40 of 60 finished and the cherry industry funded it.
Inflammation markers after daily sweet cherries
In the 30-day placebo-controlled drink trial, interferon gamma ended lower on cherry than placebo, but CRP, IL-6, IL-18 and TNF-alpha did not differ. Earlier studies in which healthy adults ate 280 g of Bing cherries a day for 28 days found C-reactive protein about 20 to 25% lower than their own starting values, with no control group, and a 12-week juice trial saw no change in CRP or IL-6.
Plasma urate after a large serving of cherries
In 10 healthy women who ate 280 g of Bing cherries after an overnight fast, plasma urate was about 14% lower 5 hours later and more urate appeared in urine; there was no control meal. A separate observational study linked recent cherry intake with fewer gout attacks, but it did not report the cherry type and cannot show cause and effect.
Night-time rest measured by wrist monitor
Short Spanish studies tracked sleep with a wrist actigraph while adults ate Jerte Valley sweet cherries or a freeze-dried cherry drink for 5 days. Sleep time and night awakenings improved versus baseline on cherry and not on a Kool-Aid placebo, and a melatonin breakdown product in urine rose, but the analysis never compared cherry with placebo directly.
Memory and verbal fluency in a 12-week juice trial in older adults
In 49 adults over 70 with mild-to-moderate dementia, 200 mL a day of anthocyanin-rich cherry juice, described as Bing sweet cherry juice, for 12 weeks was reported to improve verbal fluency and short and long-term memory scores in the cherry juice group, with a low-anthocyanin juice as control; the abstract does not state between-group results. It is one small trial in people with a diagnosed condition and has not been repeated.
Source of anthocyanins, vitamin C and potassium
Red sweet cherries carry anthocyanins, mostly in the skin, at roughly 80 to 300 mg per 100 g in many red cultivars and far less in yellow ones such as Rainier. A cup with pits (138 g) supplies about 9.7 mg of vitamin C, 306 mg of potassium, 2.9 g of fiber and 17.7 g of sugars. Melatonin is present only in nanogram amounts.
Mechanism of action
Anthocyanins and urate production in lab work
A cherry review notes that anthocyanins inhibited xanthine oxidase, the enzyme that makes uric acid, in test tubes, but the study it cites used aronia berry anthocyanins, not cherry, and the urate-lowering animal work it mentions used tart cherry juice. In people, the one sweet cherry study saw lower plasma urate with higher urinary urate after a meal, which points to more excretion, but it had no control meal.
Melatonin and tryptophan content
Sweet cherries contain melatonin in nanogram amounts (about 10 to 20 ng/g in two ripe cultivars) along with tryptophan and serotonin. In the Spanish studies a urinary melatonin breakdown product rose after cherry intake, which is the proposed link to sleep; how much the fruit's own melatonin contributes has not been measured.
Vitamin C delivered as dehydroascorbic acid
All of the vitamin C measured in Bing cherries was in the oxidized form, dehydroascorbic acid. Plasma ascorbic acid rose after a 280 g serving, showing the body converts it back to usable vitamin C.
Clinical trials
Single-group dietary study at the USDA ARS Western Human Nutrition Research Center, comparing blood values before and after 28 days of added cherries; a USDA ARS release says the California Cherry Advisory Board helped fund the research. (Kelley et al. 2006, J Nutr)
18 healthy men and women; 280 g/day of Bing sweet cherries for 28 days, with blood drawn twice before, twice during and once 28 days after.
Versus each person's pre-cherry values, C-reactive protein fell 25% and RANTES 21% (both P < 0.05) and nitric oxide 18% (P = 0.07). IL-6, its soluble receptor, ICAM-1, TIMP-2, cholesterol and lipoprotein measures, triglycerides, fasting glucose and insulin did not change. With no control group, the changes cannot be separated from time or diet effects.
Before and after study by the same USDA ARS group using a proteomics panel; PubMed tags it as a randomized controlled trial, but the abstract describes no control arm. (Kelley et al. 2013, J Nutr)
18 men and women aged 45 to 61 with modestly raised C-reactive protein (range 1 to 14 mg/L, mean 3.5 mg/L); 280 g/day of Bing sweet cherries for 28 days.
Of 89 biomarkers, 9 changed versus pre-cherry values: CRP fell 20.1%, ferritin 20.3%, PAI-1 19.9%, endothelin-1 13.7%, EGF 13.2%, IL-18 8.1% and EN-RAGE 29.0%, while IL-1 receptor antagonist rose 27.9%. 67 markers did not change and 13 were below detection. No clinical outcome was measured.
Single-dose study at the USDA ARS Western Human Nutrition Research Center with blood and urine sampled before and up to 5 hours after the meal; the abstract describes no control meal. (Jacob et al. 2003, J Nutr)
10 healthy women aged 22 to 40; 280 g (two servings) of Bing sweet cherries after an overnight fast.
Plasma urate fell from 214 to 183 micromol/L at 5 hours (P < 0.05) and urinary urate peaked at 3 hours (350 vs 202 micromol/mmol creatinine, P < 0.01). CRP and nitric oxide fell only marginally (P < 0.1); albumin and TNF-alpha did not change. Plasma vitamin C rose, though the cherries' vitamin C was all dehydroascorbic acid. A same-day marker change, not a test of any condition.
Clinical study at the University of Extremadura, Spain, with wrist actigraphy and urinary melatonin metabolite measurements; the abstract describes no placebo or control group. (Garrido et al. 2010, J Gerontol A Biol Sci Med Sci)
Middle-aged and elderly volunteers eating each of seven Jerte Valley cherry cultivars; the abstract does not give the number of participants or the daily amount.
After each cultivar the abstract reports better actual sleep time, total nocturnal activity, assumed sleep and immobility, and higher urinary 6-sulfatoxymelatonin and total antioxidant capacity. Without a control period on a comparison food, these results show change from baseline only.
Blind, placebo-controlled, randomized crossover trial with two 5-day periods and a 1-week washout; supported by the Extremadura regional government, including an agreement with the Valle del Jerte cooperative group; authors declared no conflicts. (Garrido et al. 2013, J Nutr Health Aging)
30 volunteers: 10 aged 20 to 30, 10 aged 35 to 55 and 10 aged 65 to 85. Twice daily, a drink of freeze-dried sweet cherries equal to 141 g fresh fruit, plus maltodextrin and 1.5 g added vitamin C, or a cherry-flavored Kool-Aid placebo.
On the cherry product, actigraph sleep measures (for example actual sleep time and number of awakenings) improved versus baseline in all age groups, and urinary 6-sulfatoxymelatonin and night-time IL-1 beta, TNF-alpha and IL-8 rose; on placebo none changed. The statistics compared each period with its own baseline, not cherry with placebo directly, and the cherry drink also contained 1.5 g of added vitamin C per dose.
Single-blind randomized placebo-controlled trial at Texas A&M University, funded by the Northwest Cherry Growers and Washington State Fruit Commission, with cherry ingredients donated by suppliers; authors declared no conflicts. Registered only after it ended (NCT05586386), listing gut bacteria, liver enzymes and cognition as primary outcomes, inflammatory markers as secondary and blood pressure not at all. (Arbizu et al. 2023, Nutrients)
60 adults with a BMI of 30 to 40 randomized; 40 completed (19 cherry, 21 placebo). 200 mL twice a day of a drink made from dark sweet cherry concentrate plus cherry powder, or a placebo drink matched for sugar content, color and taste.
At 30 days systolic blood pressure was lower on cherry than placebo (p = 0.05), but the cherry group had started lower (about 115 vs 121 mmHg) and the treatment by time interaction was not significant (p = 0.49). Diastolic pressure fell more on cherry (about -4.5 vs +0.9 mmHg, p = 0.04), although placebo started higher. Interferon gamma was lower on cherry (p = 0.001), while CRP, IL-6, IL-18, TNF-alpha and RANTES did not differ. Lipids, glucose and liver enzymes did not differ, and one third of those randomized dropped out.
Randomized controlled trial at the University of Wollongong, Australia, with cognition as the main outcome and blood pressure and inflammation as secondary outcomes; funding is not stated in the abstract. (Kent et al. 2017, Eur J Nutr)
49 adults over 70 with mild-to-moderate dementia; 200 mL/day of cherry juice (described in a later review as Bing sweet cherry juice) or a control juice with negligible anthocyanins (apple juice per the review).
The abstract reports improvements in verbal fluency (p = 0.014), short-term memory (p = 0.014) and long-term memory (p <= 0.001) in the cherry juice group, and a reduction in systolic blood pressure in the cherry group (p = 0.038) with only a trend for diastolic pressure (p = 0.160). CRP and IL-6 did not change. A single small trial in people with a diagnosed condition.
Observational case-crossover study run online by Boston University, comparing cherry intake in the 2 days before attacks with 2-day control periods in the same people; funded by NIAMS, the Arthritis Foundation and the American College of Rheumatology. (Zhang et al. 2012, Arthritis Rheum)
633 people with gout followed for 1 year; self-reported servings of cherries (half a cup or about 10 to 12 cherries) and cherry extract; the cherry type was not reported.
Cherry intake over 2 days was linked with 35% lower odds of an attack (OR 0.65, 95% CI 0.50 to 0.85) and cherry extract with OR 0.55 (95% CI 0.30 to 0.98). Uric acid was not measured. As an observational study it cannot show that cherries caused the difference, and it is not evidence for treating gout.