Cherries: Cherries are a great source of naturally occurring melatonin, a hormone that helps regulate your sleep cycle. In fact, one study showed that adults who drank two daily glasses of tart cherry juice slept on average 40 minutes longer with greater sleep efficiency. The juice has also been shown to help reduce the severity of insomnia in some sufferers. Add some dry tart cherries to a trail mix to snack on during the day, or drink up to two glasses of tart cherry juice to see the benefits for yourself.