Table 1. Association of the genetic risk score with BMI and risk of obesity adjusted for age, age², and sex in the combined sample of all 11 cohorts and further stratified by physical activity level.

Physical activity levela	N	βb (SE)	P-value	βweight c	n (normal weight)/n (obese)	ORd (95% CI)	P-value
Overall	111,421	0.161 (0.006)	2.1×10−176	465	52,714/16,506	1.081 (1.069, 1.094)	1.1×10−42
Inactive	27,847	0.186 (0.006)	4.8×10−47	538	11,451/5,696	1.090 (1.072, 1.107)	2.3×10−25
Moderately inactive	31,956	0.160 (0.011)	3.8×10−51	462	14,978/4,695	1.052 (1.031, 1.075)	1.6×10−06
Moderately active	27,440	0.155 (0.011)	1.1×10−46	478	13,859/3,441	1.093 (1.073, 1.114)	8.5×10−21
Active	24,178	0.143 (0.011)	5.6×10−40	413	10,945/4,155	1.095 (1.071, 1.120)	1.7×10−15

^aPhysical activity was estimated according to the Cambridge Physical Activity Index (CPAI), which categorizes total physical activity levels on a four level scale.

^bIncrease in BMI units (kg/m²) for each additional unit increase in the GRS (equivalent to one additional risk allele).

^cβ converted to body weight (g) for a person 1.70 m tall.

^dhigher odds of being obese (≥30 kg/m²) versus normal weight (18.5≤BMI<25 kg/m²) for each additional BMI-increasing allele.