Metabolic mediators of the relationships between modifiable risk factors and CRC. A) Phylum Actinobacteria effect on CRC mediated by plasma galactonate and urinary lactose. B) Class Actinobacteria effect on CRC mediated by plasma galactonate and urinary lactose. C) Smoking initiation effect on CRC mediated by plasma 1-lignoceroyl-GPC (24:0), 1-linoleoyl-2-linolenoyl-GPC (18:2/18:3)*. D) BMI effect on CRC mediated by plasma 1-lignoceroyl-GPC, mannonate*, mannose, deoxycholic acid glucuronide, 1,2-dilinoleoyl-GPC(18:2/18:2), and 1-linoleoyl-2-linolenoyl-GPC(18:2/18:3)*. E) Waist to hip ratio effect on CRC mediated by plasma 1,2-dilinoleoyl-GPC (18:2/18:2), hydroxypalmitoyl sphingomyelin (d18:1/16:0(OH))**, and mannose. F) Fasting insulin effect on CRC mediated by plasma mannose. BMI = body mass index; CRC = colorectal cancer.