Adding DHA and AA to infant formula yields no significant benefit.
A meta-analysis by researchers at Yale University shows that infant formula supplemented with long-chain polyunstatured fatty acids, including docosahexaenoic acid (DHA) and arachidonic acid (AA), was no better than other formulas for infant cognition. The Yale researchers compared supplemented and unsupplemented soy and cow's milk-based formulas.
PositiveTip: Through the first year, breastfeeding is the optimal infant nutrition. If you must use formula, fatty acid supplemented formula appears to provide no advantage.