People who get at least 44.8% of their daily calories from ultra-processed foods have a higher likelihood of developing precancerous growths in the colon and rectum, especially more advanced or located in the upper part of the colon.

We analyzed the available evidence and found that people who get at least 44.8% of their daily calories from ultra-processed foods show a higher likelihood of developing precancerous growths in the colon and rectum, particularly more advanced ones or those located in the upper part of the colon [1]. These growths, called colorectal adenomas, are not cancer but can sometimes turn into cancer over time if not removed. What we’ve found so far is based on one assertion that links higher intake of ultra-processed foods — like packaged snacks, sugary drinks, and ready-to-eat meals — to an increased chance of these early warning signs in the colon. There were no studies in our review that contradicted this pattern. The evidence we’ve reviewed leans toward a connection between how much of these foods someone eats and the risk of developing these precancerous changes. Ultra-processed foods are typically high in added sugars, unhealthy fats, salt, and artificial additives, and low in fiber and nutrients. While we don’t know exactly how they might contribute to these growths, the pattern in the data suggests that diets heavy in these items may be associated with changes in the colon that could matter for long-term health. Our current analysis shows this link, but we don’t yet know if cutting back on these foods would reduce the risk — or if other lifestyle factors might be involved. More research is needed to understand the full picture. For now, if you’re concerned about colon health, paying attention to how much of your diet comes from ultra-processed foods might be a practical step — not because it’s proven to prevent growths, but because it’s one part of a pattern we’ve seen in the data.