Walnuts are the round, single-seed stone fruits of the walnut tree. They ripen between September and November in the northern hemisphere. The brown, wrinkly walnut shell is enclosed in a husk. Shells of walnuts available in commerce usually have two segments (but three or four-segment shells can also form). Walnuts are a great source of alpha-linolenic acid (ALA), an omega-3 fatty acid that is important for reducing inflammation. In fact, it is the only nut significantly high in these omega-3 fatty acids. Their anti-inflammatory compounds may reduce the risk of heart disease.
