Banana
If you are sad and sleepless, try munching two or three bananas before going to bed. Banana is a rich source of magnesium that helps reduce anxiety and improves sleep. They also contain tryptophan, an amino acid that is converted into serotonin in your body. Large amounts of vitamins, minerals, carbohydrates, natural sugars and potassium present in bananas make it a nutritious snack that helps the body's circulatory system deliver oxygen to brain.