A new paper using data from the DIAMOND (DHA Intake And Measurement Of Neural Development) study has shown that supplementation of infant formula with docosahexaenoic acid (DHA) and arachidonic acid (ARA) during the first year of life has a protective effect against allergy in early childhood. The allergy status of the mother was shown to have a profound effect on the nature of the protection for the infant.
The DIAMOND (DHA Intake And Measurement Of Neural Development) study was conducted in Kansas City, USA, with a large cohort of healthy, full term babies that were fed exclusively with infant formula. An intervention of various levels of docosahexaenoic acid (DHA) and arachidonic acid (ARA) during the first year of life were made. The results have led to a range of publications. As an example, LCPUFA supplementation (DHA/ARA) in infancy was found to predict higher length percentiles in infancy and higher weight and stature-for-age percentiles from two to six years, but most importantly, no increase in BMI (2).
Over the past 30 years, the development of allergy in infant and young children has increased markedly. Dietary factors are thought to be an important contribution to this, particularly the change in type and quantity of lipids consumed. A recent paper (3) has suggested that an increase in the dietary ratio of omega-6 fatty acids to omega-3 fatty acids is an important factor in explaining this increase. However, little research has been done on the influence of lipids in an infant diet and the subsequent development of allergy.
It has been shown that babies fed infant formula containing recommended levels of DHA and ARA have similar immune cell distribution and cytokine profiles to breast-fed infants (4). There is a single study that used interventions of DHA and ARA in infant formula during the first year of life that found that incidence of physician confirmed allergic illnesses was reduced during the first three years of life (5).
The new study (1) used a subset of 91 normal children from the DIAMOND trial and assessed development of allergic illnesses over their first six years. Potential confounders such as smoking, pets, siblings etc. were accounted for in the statistical analysis. The children had received either a control formula or an intervention formula containing 0.64% ARA (as total fatty acids) and either 0.32, 0.64 or 0.96% DHA (as total fatty acids). The results showed that in the first year of life, the LCPUFA intervention group had less total allergy, less skin allergy and increased illness-free time (as applied to allergic illnesses). In the first four years of life, the LCPUFA group had a 64% reduction in skin allergic illnesses where the mother did not suffer from allergy. Curiously, where mothers had reported that they suffered from an allergy, the LCPUFA group showed a 74% reduction in wheezing and asthma, whereas there was no reduction if the mothers had no allergy.
Whilst this was a relatively small study, it does suggest that supplementation of infant formula with DHA and ARA during the first years of life provides protection against the development of allergic illness during childhood, but that the allergic status of the mother is an important factor in the nature of that protection.