Protein intake during pregnancy and offspring body composition at 6 years: the Generation R Study

PURPOSE: Intra-uterine exposure to protein may affect body composition and may increase the prevalence of childhood adiposity. Therefore, we examined whether protein intake during pregnancy is associated with offspring body composition at the age of 6 years and whether associations differ for animal protein and vegetable protein. METHODS: We included 2694 Dutch mother–child pairs participating in a prospective population-based cohort in Rotterdam, the Netherlands. Energy-adjusted protein was measured in pregnancy using a food-frequency questionnaire and analyzed in quartiles. At a mean age of 6.1 ± 0.4 years, we measured children’s body mass index, and fat-free mass index and fat mass index using dual-energy X-ray absorptiometry. Outcomes were standardized for age and sex. BMI was used to classify children’s overweight status. RESULTS: After adjustment for sociodemographic and lifestyle factors, a higher maternal protein intake was associated with a higher children’s fat-free mass index [difference 0.14 standard deviation (95 % CI 0.03, 0.25) for highest vs. lowest quartile of protein intake], but not with children’s fat mass index or body mass index. Comparable associations were found for animal protein and vegetable protein. Maternal protein intake was not associated with children’s overweight. CONCLUSIONS AND RELEVANCE: This study suggests that higher protein intake during pregnancy is associated with a higher fat-free mass in children at the age of 6 years, but not with their fat mass. Our results do not suggest specific recommendations regarding maternal protein intake during pregnancy to prevent overweight in the offspring. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00394-016-1255-4) contains supplementary material, which is available to authorized users.