Try having one of these snacks one hour before bedtime. Kiwis are rich in serotonin, a hormone and neurotransmitter that promotes sleep. Cheese and whole-wheat-crackers contain 80% carbohydrates and 20% protein, the best ratio for boosting serotonin. But skip aged cheeses, such as Parmesan—they have an amino acid that can raise levels of stimulating chemicals. Tart cherry juice contains high levels of the hormone melatonin, which may help you sleep longer and more soundly.

Michael Breus, PhD, author of The Sleep Doctor’s Diet Plan, writing in Shape.