NEW YORK, Dec 16: A new US government-led study suggests that popular cooking oils used in ultra-processed Western diets may be contributing to a rise in colon cancer cases. The research points to unhealthy seed oils, such as sunflower, grapeseed, canola, and corn oils, which may trigger chronic inflammation in the body.

Until now, evidence linking cooking oils to colon cancer has been inconclusive. However, this recent study identified seed oils as a potential contributing factor by examining tumors from over 80 individuals, aged 30 to 85, diagnosed with colon cancer. The study found that these tumors contained higher levels of bioactive lipids—small oily molecules produced when the body metabolizes seed oils—compared to healthier fats. The findings were published in the Gut journal.

These bioactive lipids not only increase inflammation but also hinder the body’s natural healing processes, promoting tumor growth. In contrast, oils rich in omega-3 fatty acids, such as those found in avocados and olives, are considered healthier alternatives.

Dr. Timothy Yeatman, a renowned physician-scientist, emphasized the need to reevaluate aspects of the Western diet, including added sugars, saturated fats, ultra-processed foods, chemicals, and inflammatory seed oils. Dr. Yeatman, who is also an associate center director for Translational Research and Innovation at the TGH Cancer Institute, explained, "It is well known that patients with unhealthy diets have increased inflammation in their bodies. We now see this inflammation in the colon tumors themselves. Cancer is like a chronic wound that won’t heal. If your body is living off daily ultra-processed foods, its ability to heal that wound decreases due to the inflammation and suppression of the immune system, which ultimately allows the cancer to grow."

However, leading U.S. health institutions have clarified that consuming moderate amounts of seed oils as part of a balanced diet has not been shown to cause cancer.