Buckwheat
A natural mood-calmer, buckwheat is high in relaxing tryptophan, providing 25 percent of your recommended allowance in a one-cup serving. Buckwheat is also a good source of magnesium, with 229 mg per serving. (Though some forms of cooking drop the magnesium content.) Technically a fruit seed, buckwheat is gluten-free and high in fiber, so it’s a great grain substitute. Throw it in soups or stews, or cook it and add it to salads. You can even boil it up as a hot breakfast cereal, much like grits or cream of wheat.