Associations between maternal antioxidant intakes in pregnancy and infant allergic outcomes.

Plain Language Summary

This research studied the maternal intake of antioxidants (carotene, vitamin C, vitamin E, copper and zinc) during pregnancy and the effect on allergic outcomes during early infancy (eczema, food allergies, allergic sensitisation and wheeze) at 1 year of age. The study included 300 mother and child pairs from a pregnancy cohort in Western Australia from 2005 to 2008. The pregnant women had a family history of allergic rhinitis, asthma, eczema, food or other allergy. A post-natal randomised trial allocated either 650mg fish oil (280mg docosahexaenoic acid (DHA) and 110mg eicosapentaenoic acid (EPA)) or a placebo of olive oil for the first 6 months of life. The study also examined the effect of maternal diet during pregnancy. Demographic information was collected, and a semi quantitative food frequency questionnaire covering 212 foods was completed during the final trimester of pregnancy. Clinical outcome measures of the infants were taken at 12 months of age via a detailed history and examination. Eczema, IgE mediated food allergies and allergic sensitisation were the most common clinical outcomes of the study. The majority of pregnant women met the recommended daily intakes of antioxidants apart from vitamin E and zinc. At 12 months of age there was no difference in the occurrence of clinical outcomes between the fish oil and placebo groups. Higher dietary vitamin C in the mothers was associated with reduced risk of any diagnosed allergic disease when children were a year old, and also a reduced risk of wheeze. Higher copper intake was related to reduced risk of wheeze and development of early allergic disease. However, this was only seen in relation to nutrients from food rather than supplements. It was noted that there were no significant associations between early allergic responses/disease and dietary intake of carotene, vitamin E and zinc. In the group studied, the majority of mothers used some vitamin/mineral supplementation during pregnancy. There was no statistically significant association between carotene, vitamin E and zinc intake in pregnancy and risk of developing any allergic disease. Women reported intakes of dietary vitamin C were above the daily recommended intake of 60mg, and authors noted that allergic outcomes were not affected by vitamin supplementation.