Food must supply a balance of nutrients to support both brain and body. The human brain makes us uniquely human. Essential fatty acids are part of the metabolic pathways that define tissue structure and function. Omega-6 (O6) linoleic acid (LA6) has long been known to be required for skin structure, and as a precursor for inflammatory, thrombotic, immune, and other signaling molecules. Omega-3 (O3) alpha-linolenic acid (ALA3) and particularly its long chain product docosahexaenoic acid (DHA3) has a key structural role in the brain, retina, and related neural tissue. In the 20th century western world, inexpensive, high quality oils primarily from LA6-rich/O3-poor vegetable seed oils became dominant fats produced by the food industry. Provision of LA6-rich/O3-poor oils as the sole source of fat in the diets of pregnant animals causes O3 deficiency and poor brain development, primarily because high LA6 antagonizes metabolism of all O3, creating an artificial metabolic demand for O3. Data developed over the last 2~3 decades show that provision of low LA6 combined with preformed DHA3 optimizes brain function. Recent studies emphasize the importance of nutrition to support brain development, with newer findings showing particular importance of fatty acid balance in malnourished children. The World Health Organization (WHO) through the Codex Alimentarius (“Code for Food”) is increasingly recognizing the primacy of brain health and in part on that basis recently acted to recommend balanced fat for Ready-to-Use-Therapeutic Foods used to treat children with severe acute malnutrition. Similar principles are likely to be important in older persons. Industry now has the tools to adjust the composition of oils to support brain health throughout the life cycle.