Tart cherry juice seems to be tailormade for people seeking a better night's sleep. Adults who daily drank two glasses of tart cherry juice slept 39 minutes longer and had up to six percent increase in overall sleep efficiency (less non-sleep time in bed), compared to when they drank a non-cherry, fruit cocktail. In a study conducted by Britain's Northumbria University, healthy adults drank two servings of tart cherry juice concentrate or a non-cherry fruit drink for seven consecutive days, one serving each in the morning and at bedtime, the European Journal of Nutrition reports.Researchers tracked the participant's sleep habits and after drinking the cherry juice, they found significant improvements in sleep behaviour, most notably longer sleep time, less daytime napping and increased overall sleep efficiency. They attribute the sleep benefits to the melatonin content of the red super fruit - a powerful antioxidant critical for sleep-wake cycle regulation, according to a university statement. Each serving of the tart cherry juice concentrate was estimated to contain the equivalent of 90-100 tart cherries, providing a significant level of melatonin in the juice and ultimately in the bodies of the participants. Previous research has supported the benefits of tart cherries as a sleep aid - a potentially wide-reaching benefit.