The Study
Identifying Metabolomic Mediators of the Physical Activity and Colorectal Cancer Relationship
This study found that people who exercise more tend to have a certain chemical in their blood that’s also linked to lower cancer risk. But it doesn’t prove that exercise causes the chemical to change and then prevent cancer — maybe people who are already healthier (and less likely to get cancer) just happen to exercise more.
Analysis score
Maximum 58 for a case-control study.
Where the score came from
People who move more have a lower chance of getting colon cancer, and scientists found one specific fat molecule in their blood that might explain a small part of why.
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 558 / 100
Quality score
Researchers compare people who have a condition (cases) with similar people who do not (controls), looking back in time for differences in exposure. Useful but more prone to bias.
Key takeaways
Summary
Based on the study abstract and findings.
- 1The effect is real but small — most of the benefit from exercise still isn't explained by this molecule, so other factors are likely more important.
- 2Moving more = 10% lower cancer risk.
- 3One fat molecule (C34:3) explains 7.4% of that benefit.
Score breakdown, methodology, conflicts of interest, evidence analysis & raw study data
Publication
Journal
Cancer Epidemiology, Biomarkers & Prevention
Year
2025
Authors
N. Papadimitriou, N. Kazmi, K. Tsilidis, R. Richmond, B. Lynch, B. Bendinelli, Fulvio Ricceri, M. Sánchez, Camino Trobajo-Sanmartín, P. Jakszyn, Vittorio Simeon, G. Severi, V. Perduca, Thérèse Truong, Pietro Ferrari, P. Keski-Rahkonen, E. Weiderpass, F. Eichelmann, Matthias B. Schulze, V. Katzke, R. Fortner, A. Heath, D. Aune, R. Harewood, C. Dahm, Adrian Llorente, Marc J. Gunter, N. Murphy, Sarah J Lewis
Related Content
Claims (6)
People who are more physically active have a 10% lower risk of developing colorectal cancer compared to those who are less active, based on standardized activity measurements.
A specific set of 24 metabolic markers related to physical activity does not explain the observed link between physical activity and colorectal cancer risk, as the statistical mediation effect is not significant.
A specific lipid molecule called phosphatidylcholine acyl-alkyl C34:3 may explain a small portion of why people who are more physically active have a lower risk of colorectal cancer, but this connection becomes weaker when there is a longer delay between activity and cancer diagnosis.
In studies linking physical activity to colorectal cancer risk, the connection appears weaker when people diagnosed with cancer shortly after blood tests are removed, suggesting that early, undetected cancer may affect activity levels rather than activity causing cancer.
People who are more physically active tend to have a lower risk of developing colorectal cancer, while those who spend more time sitting have a higher risk.
People who are more physically active tend to have higher levels of a specific lipid molecule called phosphatidylcholine acyl-alkyl C34:3 in their blood, based on statistical analysis of metabolic data.
Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.