The risk of colorectal adenomas increased by 2% [1.02 (0.97-1.08)] for each 1 mg/L increment in circulation CRP levels (eight studies [8, 10, 17, 20, 22–25] including 4,981 cases), 9% [1.09 (0.91-1.31)] for each 1 ng/L increment in circulation IL-6 levels (five studies [8, 13, 15, 20, 25] including 1,763 cases), and 6% [1.06 (0.93-1.21)] for each 1 pg/mL increment in circulation TNF-α levels (four studies [12–13, 18, 25] including 1,452 cases), respectively. Here, TNF is linked to colorectal adenoma.