Abstract
Body composition and fat distribution were found to display differential effects on the incidence and mortality of chronic disease. However, it remained unclear whether there is an interaction between lifestyle factors and genetic susceptibility on body composition and fat distribution. This study investigated the associations of lifestyle and genetic factors with body composition and fat distribution among 121 664 women from the UK Biobank cohort study. Women with a favourable lifestyle had lower BMI (BMI, -7·72 % (95 % CI: -7·93 %, -7·51 %)), fat mass index (FMI, -15·70 % (95 % CI: -16·09 %, -15·30 %)), fat-free mass index (FFMI, -2·86 % (95 % CI: -2·98 %, -2·74 %)), arm fat ratio (AFR, -5·19 %, (95 % CI: -5·38 %, -5·00 %)) and trunk fat ratio (TFR, -0·73 %, (95 % CI: -0·84 %, -0·62 %)) but higher leg fat ratio (LFR, 2·30 % (95 % CI: 2·16 %, 2·44 %)) than those with an unfavourable lifestyle. Significant interactions between lifestyle factors and genetic susceptibility on BMI, FMI and AFR were observed (Pinteraction < 0·05). Among women with a high genetic susceptibility to body composition or fat distribution, those with a healthy lifestyle still had a lower BMI, FMI, FFMI, AFR and TFR and higher LFR (Ptrend < 0·001). Women who adhere to a favourable lifestyle tend to have healthy body composition and fat distribution, and this association is consistent across all strata of genetic risk.