The Study
Body Mass Index and Risk of Colorectal Cancer Incidence and Mortality in Asia
This study looked at lots of people over many years and found that those with higher body weight tended to get colorectal cancer more often. But it didn’t make people gain weight to test it — it just watched what happened naturally, so we can’t say weight definitely causes cancer, only that they often happen together.
Analysis score
Maximum 72 for a cohort study.
Where the score came from
This study looked at hundreds of thousands of Asians over 15 years to see if being heavier means more chance of getting or dying from colon cancer.
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.
- 1Yes — even modest weight gain above normal BMI raises cancer risk, and obesity drastically increases death risk for Asian men.
- 2People with BMI over 30 had 32% more colon cancer and 38% more deaths from it.
- 3Men with BMI over 30 had 87% higher death risk; women did not.
- 4Even overweight people (BMI 25–27.5) had 9% higher cancer risk.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
JAMA Network Open
Year
2024
Authors
P. Paragomi, Zhongjie Zhang, S. Abe, Md Rashedul Islam, Md. Shafiur Rahman, E. Saito, Xiao-Ou Shu, Bashir Dabo, Y. Pham, Yu Chen, Yutang Gao, Woon-Puay Koh, N. Sawada, R. Malekzadeh, R. Sakata, Atsushi Hozawa, Jeongseon Kim, Seiki Kanemura, C. Nagata, San-Lin You, Hidemi Ito, Sue K. Park, Jian-Min Yuan, Wen-Harn Pan, W. Wen, Renwei Wang, Hui Cai, S. Tsugane, A. Pourshams, Y. Sugawara, K. Wada, Chien-Jen Chen, I. Oze, A. Shin, H. Ahsan, P. Boffetta, K.S. Chia, K. Matsuo, Y. Qiao, N. Rothman, Wei Zheng, M. Inoue, D. Kang, Hung N. Luu
Related Content
Claims (6)
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.
In Asian men, having a BMI over 30 is linked to an 87% higher chance of dying from colorectal cancer compared to having a BMI between 23 and 25. This link is not seen in Asian women, suggesting the relationship between body weight and colorectal cancer death differs by sex.
Among people of Asian descent, having a body mass index (BMI) between 25.0 and 27.5 is linked to a 9% higher rate of developing colorectal cancer compared to those with a BMI between 23.0 and 25.0.
Asian adults with a BMI above 30 have a 32% higher chance of developing colorectal cancer than those with a BMI between 23.0 and 25.0, based on long-term population data.
People with higher body mass index (BMI) have a greater rise in colon cancer rates compared to rectal cancer rates, suggesting that excess body fat may affect colon tumors more than rectal tumors.
People with higher body mass index tend to have higher rates of death from colorectal cancer in China, Japan, and Iran, but this link is not clear in South Korea, which may be due to differences in how the studies were done or other unmeasured factors.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.