Tart Cherry Juice

Cherries are a member of the stone fruit family and can meaningfully contribute to dietary intakes of dietary fiber, vitamin C, and potassium.^[4] Stone fruit are fruits that consist of a thin outer layer, edible flesh, and a hard stone that encloses a seed. Cherries are grouped into two major types: sweet (Prunus avium L.) and tart (Prunus cerasus L.) cherries.^[5] The latter are processed to produce tart cherry juice and tart cherry juice concentrate. The scientific interest in tart cherry juice is primarily due to its rich content of polyphenols, particularly anthocyanins, which possess antioxidant and anti-inflammatory properties.^[6]

Supplementation with tart cherry products has been found to improve recovery from both prolonged aerobic and resistance exercise, including small reductions in perceived muscle soreness and some markers of inflammation, as well as a more rapid return to baseline levels of muscular strength and power.^[3] Tart cherry products may also provide a small benefit for endurance exercise performance.^[2]

Evidence from a few studies suggests that tart cherry juice has the potential to improve some sleep quality parameters, both in older adults with insomnia^[7] and younger adults without sleep problems.^[8][9]

Randomized controlled trials typically do not report adverse effects associated with consumption of tart cherry juice. Case reports of acute kidney injury from daily consumption of cherry juice concentrate, including black cherry concentrate^[10] and an unspecified cherry juice concentrate,^[11] have been reported in people with chronic kidney disease (CKD). Whether similar issues in people with CKD could carry over to tart cherry juice intake is unclear, but plausible.

The mechanism by which the polyphenols in cherry juice concentrate reduce inflammation (i.e., by inhibiting cyclooxygenase enzymes) may also reduce kidney function in people with CKD.^[10][11] Because tart cherry juice concentrate is rich in many of the same polyphenols as other cherry juice concentrates, it could also potentially be harmful for people with CKD.

Another potential drawback of tart cherry juice is its carbohydrate content. It contains polyols,^[12] a specific type of carbohydrate that can be harmful to people with irritable bowel syndrome.^[13] A cup of tart cherry juice contains about 130 kcal, so it can theoretically contribute to weight gain, though studies have reported that supplementation with tart cherry juice does not affect BMI or fat mass.^[14]

High doses of antioxidants can also impair exercise-induced adaptations,^[15] so long-term supplementation with tart cherry juice could be detrimental for athletes, particularly in the off-season, when the goal is to maximize exercise-induced adaptations. However, direct evidence is needed to determine whether the commonly consumed dose of tart cherry juice is large enough to have this effect.

The benefits of tart cherry juice are thought to primarily come from its abundant polyphenol content, most notably anthocyanins, which possess potent antioxidant and anti-inflammatory properties.^[16]

Tart cherry juice may improve sleep by increasing melatonin levels,^[9] as tart cherries are a relatively rich source of melatonin,^[17] and they seem to increase the availability of tryptophan,^[7] which is used to synthesize melatonin in the body.

Tart cherry juice may enhance endurance exercise performance by elevating muscle antioxidant capacity, thus minimizing the production of oxidants during exercise, which can depress force production and contribute to fatigue.^[18] Additionally, as a source of low-glycemic-index carbohydrate, tart cherry juice might support performance by promoting fat oxidation and allowing sustained carbohydrate availability during exercise,^[19] but it’s unclear whether tart cherry juice is superior to other sources of low-glycemic-index carbohydrate. Another way tart cherry juice might benefit endurance exercise performance is by increasing blood flow and oxygen delivery to the working muscles.^[2]