Why is there interest in adding DHA and ARA to infant formulas?

While infants can make these fatty acids from other ("essential") fatty acids in their diet, including the fatty acids in infant formulas, some studies suggest that some infants, such as premature infants, may benefit from direct consumption. Other studies suggest no benefit. It is known that long-chain polyunsaturated fatty acids (DHA in particular) accumulate in brain and eye of the fetus, especially during the last trimester of pregnancy. These fatty acids are also found in the fat of human breast milk. Blood levels of DHA and ARA are typically higher in breast-fed infants than in infants fed formulas not containing these fatty acids. For these reasons, some infant formula manufacturers and consumers are interested in providing DHA and ARA directly to infants. These manufacturers and consumers argue that adding oils containing these fatty acids to the fats and oils already in infant formula will provide an infant with both pre-formed DHA and ARA and the essential fatty acids an infant needs to make its own DHA and ARA.