A method is provided for fortifying a seed, grain, nut, bean, or the like with an essential fatty acid such as docosahexaenoic acid or eicosapentaenoic acid. Using the method, it is possible to produce seeds that can be used as a dietary source of that essential fatty acid. A seed that has been soaked in an aqueous mixture containing an essential fatty acid so as to become fortified with the fatty acid, and a food product formed using the seed are also provided.