Compositions containing the fatty acid docosahexaenoic acid (DHA) in combination with at least one vitamin and mineral are provided to supplement nutrition in a mammalian diet. DHA is present in the composition in concentrated amounts, advantageously in a carrier such as marinol oil, to allow for quantities of DHA sufficient to supply expectant and new mothers and their children as recommended on a daily basis. This DHA may also be used to treat a variety of disorders in children and adults. The compositions advantageously include vitamins, minerals, and optionally other nutrients to provide a nutritional supplement which may be convenient to swallow and taken once a day.