LAUSR

The inception of allergic diseases depends on complex interactions between genetic and environmental fac-tors including diet. 1 Even though maternal dietary intake during pregnancy has been associated with the health of newborn infants, 2 the effect of maternal diet on the risk of developing allergic diseases and infections by the child remains to be elucidated. Within this frame, COPSAC investigators have contributed significantly to our existing knowledge in the field. In one of the pioneering studies, in a double- blind randomized controlled trial, Bisgaard et al. 3 found that supplementation with n- 3 long- chain polyunsaturated fatty acid (n- 3 LCPUFA) during the third trimester of pregnancy reduced the risk of persistent wheeze or asthma and lower respiratory tract infections in the offspring. A combined analysis of two trials (VDAART and COPSAC 2010 ) found that high-dose vitamin D supplementation in pregnant women significantly reduced the risk of asthma/recurrent wheeze in offspring. 4 Diet supplementation of N- 3 LCPUFA and high- dose vitamin D during pregnancy was further analyzed by Brustad et al., 5 which demonstrated an association with reduced risk of croup in early childhood. However, the potential effects of diet- related metabolites transferred from mother to child during both the prenatal and postnatal periods were largely unknown.