Maternal protein intake during pregnancy and offspring overweight 20 y later

Background: Animal studies have shown that protein intake in pregnancy may influence offspring fat metabolism and adiposity. The macronutrient ratio in human pregnancy appears to be important for offspring glucose tolerance; however, less is known about the influence on offspring adiposity. Objective: We examined the relation between maternal dietary protein intake during pregnancy and offspring anthropometric measures and biomarkers of adiposity and glucose metabolism. Design: We used a prospective cohort of 965 Danish pregnant women recruited in 1988-1989 with offspring follow-up at 19-21 y. Macronutrient intake was collected in gestational week 30, and we divided protein according to its source (animal and vegetable including cereals). Offspring body mass index (BMI; in kg/m(2)) and waist circumference were recorded at follow-up (n = 695-697), and biomarkers were quantified in a subset (n = 443) of participants. We used multivariable linear and log-binomial regression to calculate effect estimates and 95% CIs for a 1:1-g substitution of carbohydrates for protein. Results: Offspring mean (+/- SD) BMI was 22.1 +/- 3.3 and 22.8 +/- 2.9 for women and men, respectively. The prevalence of overweight (BMI >= 25) was 16.9% for women and 19.1% for men. We showed that a 1:1-g substitution of animal protein for carbohydrates increased risk of BMI >= 25 in female [quartile 4 compared with quartile 1: risk ratio (RR): 3.36; 95% CI: 1.52, 7.42] and male (quartile 4 compared with quartile 1: RR: 2.22; 95% CI: 0.92, 5.35) offspring. These results appeared to be accounted for by protein from meat sources. The results could not be explained by postnatal risk factors. Conclusions: Protein from animal sources, primarily meat products, consumed during pregnancy may increase risk of overweight in offspring; this association appeared to be stronger for female offspring. Because of the lack of information on postnatal exposure in this cohort, these results are hypothesis-generating and need to be replicated in other cohorts.