One of the most concerning trends in modern medicine is the rapid rise of colorectal cancer in people under the age of 50.
The explanatory models have so far been relatively simple: diet, overweight, sedentary living, smoking. But the picture is becoming more complex.
A recently published study in Nature Medicine uses epigenetic analyses to "read" individuals' lifetime exposures, and identifies patterns linked to cancer developing at younger ages. The results confirm parts of what we already know. But they also point to something larger.
Exposome: the sum of exposures
The study is based on the concept of the exposome: the combined effect of everything we are exposed to throughout life, from diet and lifestyle to environmental factors.
By analysing DNA methylation, the researchers identify "fingerprints" of these exposures.
Beyond diet and tobacco, a clear association is identified with pesticides, particularly the herbicide picloram. Regions with higher exposure showed a higher incidence of early colorectal cancer, even after adjusting for other factors.
It is important to be clear: this is an association, not proof of a causal relationship. But the signal is robust, and hard to ignore.
What does this mean?
It strengthens the hypothesis that the increase is not driven by a single factor, but by an accumulated biological burden over time, often beginning early in life.
It also shifts the focus from lifestyle alone to biological exposure and individual risk profile.
Implications for screening
For clinical practice, this raises important questions:
- Should we identify risk earlier?
- Should screening start earlier in certain groups?
- How do we catch individuals before symptoms appear?
There are still no simple answers. But the direction is clear: the prevention of the future will increasingly be about understanding an individual's biological risk, not just general guidelines.
At Executive Health we follow this development closely. Our starting point is the same: to identify risks early, before they become clinical. Not based on a single factor, but on the whole picture.
