Association between transitions in metabolic health and colorectal cancer across categories of body size phenotype: a prospective cohort study

Abstract Objective We aimed to investigate the associations of changes in metabolic health across categories of body size phenotype with the risk of colorectal cancer in a community‐based prospective cohort. Methods In the current study, a total of 70,987 participants were included. Changes in metabolic health across categories of body size phenotype were assessed between the health examination for the first time in the years 2006 through 2009 and a 2010/2011 health examination. A multivariate Cox proportional hazards model was used to assess the associations of changes in metabolic health across body size phenotype categories with risk of colorectal cancer. Results During the median follow‐up time of 11.04 years, 428 (0.60%) participants developed colorectal cancer. Compared with metabolically healthy normal‐weight (MHNW) participants who remained MH, the risk of colorectal cancer was increased by 144% (95% CI: 1.21–4.95) for participants with metabolically healthy obesity (MHO) who converted to a metabolically unhealthy (MU) phenotype. Participants who were MU at baseline were still at increased risk of colorectal cancer, regardless of obesity status. Conclusions The MHO phenotype was a dynamic status over time, and converting to MU during follow‐up and being initially MU were associated with having an increased risk of colorectal cancer, regardless of degree of obesity and body size phenotype.