Ketogenic diets may increase cancer risk in the small intestine

A new study from MIT researchers published in Nature suggests that a ketogenic diet may increase the risk of small intestine cancer. While the high-fat, low-carbohydrate diet has been shown to help with weight loss, it could potentially pose health risks in certain tissues. The researchers discovered that mice predisposed to intestinal cancer developed tumors more rapidly on a ketogenic diet compared to a control diet.

Additionally, these tumors appeared at similar or even higher rates than those in mice on an obesogenic high-fat/high-calorie diet. The study reveals that ketone bodies, once thought to be the driving force behind the diet's protective effect against colon cancer, are not responsible for this effect. Instead, the researchers found that tumor growth was driven by how intestinal cells metabolize dietary fat through a metabolic pathway called fatty acid oxidation.

This activation of a family of proteins called PPARs encourages stem cell proliferation, which could increase the likelihood of cancerous cells forming. The discovery highlights the importance of understanding tissue-specific effects of ketogenic diets, as the same diet can have opposite consequences in adjacent parts of the gut.

Further research is needed to fully comprehend why this dietary regimen impacts intestinal health differently.