Chia et al., 2007, found increased adenoma risk for men but not women with the highest leptin (OR = 3.3, 95% CI: 1.2–8.7; P trend = 0.01); the association was attenuated to OR = 2.3, 95% CI: 0.7–7.7, and was no longer significant with BMI adjustment [19]. This evidence concerns the gene LEP and adenoma.