Interaction between breastfeeding duration and an obesity genetic risk score to predict body fat composition in...

Although the genetic interplay with the environment has a major impact on obesity development, little is known on whether breastfeeding could modulate the genetic predisposition to obesity.

To investigate whether breastfeeding attenuates the effect of an obesity genetic risk score (GRS) on adiposity in European adolescents.

Totally 751 adolescents from the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) cross-sectional study were included, divided according to breastfeeding status into never breastfed, 1-3 months and ≥4 months. Adjusting by socioeconomic status and lifestyle factors multiple linear regression models were used to assess (1) the main effect of breastfeeding duration and (2) its interaction effect with an obesity GRS, to predict different adiposity measures.

A significant negative association between ≥4 months of breastfeeding and waist circumference (WC) z-score was observed [β (95% confidence interval), p-value] = [β = -0.189 (-0.37, -0.00), p = 0.044]. Also, significant interaction effects were observed for 1-3 and ≥4 months of breastfeeding and obesity GRS regarding body mass index (BMI) z-score [β = 0.155 (0.06, 0.24), p = 0.001] and [β = 0.108 (0.01, 0.18), p = 0.020, respectively] and fat mass index (FMI) z-score [β = 0.134 (0.04, 0.22), p = 0.003] and [β = 0.100 (0.01, 0.18), p = 0.026, respectively].

Breastfeeding modulates the association between the obesity GRS and body composition in adolescents.