Cherries are naturally high in melatonin, the primary hormone involved in governing your sleep-wake cycle. In fact, in a small clinical trial, participants drank tart cherry juice concentrate (made from Montmorency cherries) for seven days (Howatson et al., 2012). The researchers found that after just one week, the participants who drank cherry juice had significantly higher levels of melatonin in their bodies. This was associated with greater time spent in bed, higher total sleep time, and better sleep efficiency. The benefits of cherries may not be limited to cherry juice. Eating dried tart cherries also supplies a source of melatonin.