1. Meta-analysis of pooled RR comparing cancer risk of the high with low BW
We compared the highest dose of BW with the low group of each study and subsequently combined them to calculate the pooled RR. Our analysis found that the risk of six cancers we selected has a significant relationship with BW. Five of them showed that higher BW was the risk factor. (Ovarian cancer: pooled RR=1.21, 95%CI=1.01-1.44, I2=11%, p=0.34; breast cancer: pooled RR=1.12, 95%CI=1.08-1.16, I2=48%, p<0.01; colorectal cancer: pooled RR=1.20, 95%CI=1.01-1.43, I2=0%, p=0.87; prostate cancer: pooled RR=1.27, 95%CI=1.01-1.61, I2=0%, p=0.93; testicular cancer: pooled RR=1.21, 95%CI=1.03-1.43, I2=0%, p=0.84) However, higher BW were likely to be the protective factor of endometrial cancer (pooled RR=0.78, 95%CI=0.78-0.93, I2=0%, p=0.63). (Figure S2- S7)