The Study
Association of changes in obesity and abdominal obesity status with early-onset colorectal cancer risk: a nationwide population-based cohort study
This study looked at lots of people over time and noticed that those who stayed overweight or had big bellies were more likely to get colon cancer young. But it didn’t make people gain or lose weight—it just watched what happened. So we can’t say being overweight causes cancer, just that they often happen together.
Analysis score
Maximum 72 for a cohort study.
Where the score came from
This study looked at whether gaining or keeping extra weight, especially around the belly, increases the chance of getting colon cancer before age 50.
Where does this study sit?
Reviews of RCTs (Meta-analyses)
Max 100Randomized Trials
Max 90Reviews of Cohort Studies
Max 85Cohort Studies
Max 72Reviews of Case-Control Studies
Max 63Case-Control Studies
Max 58Cross-Sectional & Case Series
Max 50Expert Opinion
Max 559 / 100
Quality score
Groups of people are followed over time to see who develops an outcome. Strong for identifying risk factors and associations, but cannot prove causation as firmly as RCTs.
Key takeaways
Summary
Based on the study abstract and findings.
- 1Even small increases in risk matter for young people because colon cancer is rare before 50 — so any consistent rise in risk is important to address.
- 2People who stayed obese had a 9% higher risk; those who stayed with big waistlines had an 18% higher risk; those who gained belly fat after being slim had a 69% higher risk.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Frontiers in Medicine
Year
2023
Authors
J. Song, Ji-Yeon Seo, E. Jin, G. Chung, Y. Kim, J. Bae, Sunmie Kim, K. Han, Sun-Young Yang
Related Content
Claims (5)
People with obesity have a higher chance of developing colorectal cancer compared to those without obesity, with men showing a greater increase in risk than women.
Adults who maintain a large waist size over a two-year period have an 18% higher risk of developing colorectal cancer before age 50 compared to those who do not have persistent abdominal obesity.
People who maintain a body mass index of 25 kg/m² or higher over a two-year period have a 9% higher risk of developing colorectal cancer before age 50 compared to those who maintain a non-obese weight.
People who gain fat specifically around the abdomen after being previously lean have a slightly higher chance of developing colorectal cancer at a younger age than those who never gained excess weight.
People who consistently have excess body weight and excess fat around the abdomen have a 19% higher chance of developing colorectal cancer before age 50 compared to people who maintain a normal weight and no abdominal fat accumulation.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.