On October 5, researchers revealed a striking dual effect of high-fat, low-carb regimens on gut health. A new study shows that a ketogenic diet unexpectedly accelerates tumor growth in the small intestine of mice, even as it provides protective benefits against colon cancer.
Fat Metabolism Triggers Stem Cell Growth
The researchers traced this accelerated tumor development not to the presence of ketone bodies, but directly to how intestinal cells process high dietary fat. When breaking down fats for energy, cells activate specific proteins that prompt rapid division of intestinal stem cells. While active stem cells typically help repair tissue damage, this excessive multiplication creates more opportunities for cancerous mutations to take hold in the small intestine.
Divergent Responses in the Gut
This finding creates a complex picture of gastrointestinal health. While the colon responds positively to a keto regimen by suppressing cancer formation, the neighboring small intestine experiences the exact opposite effect. Omer Yilmaz and his team emphasize that these tissue-specific reactions highlight the danger of broadly assuming a single nutritional approach universally benefits the entire digestive tract.
Because the accelerated cell division is driven by fat oxidation rather than ketones, scientists note that commercial ketone supplements are unlikely to replicate either the harmful or protective effects seen in the Massachusetts Institute of Technology research. The team is now investigating the underlying mechanisms that cause such sharply contrasting outcomes within adjacent areas of the digestive system.