A pilot randomized controlled trial to promote healthful fish consumption during pregnancy: The Food for Thought Study

Background: Nutritionists advise pregnant women to eat fish to obtain adequate docosahexaenoic acid (DHA), an essential nutrient important for optimal brain development. However, concern exists that this advice will lead to excess intake of methylmercury, a developmental neurotoxicant. Objective. Conduct a pilot intervention to increase consumption of high-DHA, low-mercury fish in pregnancy. Methods. In April-October 2010 we recruited 61 women in the greater Boston, MA area at 12-22 weeks gestation who consumed = 200mg/d of DHA from fish, compared with 33% in the Advice arm (p=0.005) and 53% in the Advice+GC arm (p=0.0002). We did not detect any differences in mercury intake or in biomarker levels of mercury and DHA between groups. Conclusions: An educational intervention increased consumption of fish and DHA but not mercury. Future studies are needed to determine intervention effects on pregnancy and childhood health outcomes. Trial registration. Registered on clinicaltrials.gov as NCT01126762.