A new review takes a public health perspective on the importance of dietary intake of arachidonic acid (ARA) and docosahexaenoic acid (DHA) during the early years of life (1). There is now extensive scientific literature describing the contributions of both ARA and DHA to fundamental metabolic systems associated with neurological, cardiovascular and immunological health. Sadly, to date, governmental intake recommendations have been limited in regard to ARA and DHA intake in infants and young children. This is despite the strong evidence that adequate intake is essential to achieve optimum development of children – particularly in the heart, brain, eye and immune system. Indeed, the NDA (Dietetic Products, Nutrition and Allergies) panel of EFSA (European Food Safety Authority) concluded that, while ARA adequate intake from 0 to 6 months is set at 140 mg/day, there is no requirement of ARA in infant formula when DHA is present (2). This provoked a response from expert nutritionists and clinicians in the field, stating there was not evidence to support this view and that it could prove harmful to provide dietary DHA without adequate levels of ARA (3,4).
The new paper (1) comments that if infants follow the WHO recommendation of exclusive breast feeding for 6 months, they will receive an intake of 190 mg/day ARA and 130 mg/day DHA at 6 months of age (assuming breast milk intake of 850 ml/day). However, it seems the financial status of the mother is important, with the intake of ARA and DHA being 20-25 percent lower in developing countries than in high-income countries (5). In addition, it was shown that the DHA and ARA intake from complementary foods in older infants was very low in limited-resource countries, particularly so in Nepal, Bangladesh, Ethiopia and Rwanda. The authors estimated that each year nearly 22 million infants are at risk of LC-PUFA (long chain polyunsaturated fatty acid) insufficiency.
Further, the paper comments (1) that as breast milk intake tails off after the age of 6 months, it is important to make certain that ARA and DHA intake is maintained by ensuring that complementary foods (solid and liquid) provide an adequate source of both these fatty acids. The nervous system is still developing at a rapid rate at this age and both ARA and DHA are essential components of the cell walls in nervous system tissue.
Recent animal experiments (6) have shown that when DHA/EPA is fed to rat pups without any ARA, the circulating levels of ARA in brain phospholipids decreased by nearly 50 percent. A similar effect was noted in humans when infants were fed a formula with DHA but without ARA, resulting in a 25 percent reduction of ARA in blood levels (7).
The review paper (1) expresses concern that results from RCTs with null outcomes in very selective populations may be used to indicate that ARA and DHA supplementation is not necessary on a global level, despite the fact that a high proportion of children globally, particularly in low-income countries, are at risk of LC-PUFA deficiency in early life. Logic suggests that ARA and DHA addition to infant formula should be mandatory to protect infants who cannot obtain adequate intake from breast milk. Furthermore, the added levels in both infant and follow-on formula should be equal to the median global levels of DHA and ARA in breast milk.