Keto diet accelerated tumor growth in mice: fats, not ketones

An MIT study published in Nature showed that a ketogenic diet with 80% fat accelerated tumor formation in the small intestine and reduced the survival of mice with a hereditary model of familial adenomatous polyposis, while suppressing tumors in the large intestine. The mechanism is linked to fatty acid oxidation through PPAR signaling pathways and the enzyme CPT1A, rather than ketones.

Compiled by Sergey KostenchukPublished 2026-10-20Updated 2026-10-21

2026-10-20 Research

🧬 Keto diet accelerated tumor growth in mice: fats, not ketones

Omer Yilmaz's team (MIT) in Nature: a ketogenic diet with 80% fat accelerated small intestine tumor growth in mice with hereditary polyposis, reduced their survival, but suppressed large intestine tumors. The mechanism is fatty acid oxidation, not BHB ketones: CPT1A blockade suppressed adenomas.

🌍 The work challenges the "anticancer" reputation of keto: the effect is determined not by ketones, but by the diet's lipids—and it is tissue-dependent. CPT1A and PPAR are specific targets for therapy, and the "anticancer" marketing of keto supplements loses its basis.

👤 On a keto diet? This is not a reason to quit: the experiments were conducted on mice, not humans. The same diet can act oppositely in adjacent tissues—there is no "universally beneficial" diet.

Source 1: https://www.technologyreview.com/2026/10/20/1145279/a-reason-to-eat-carbs/ Source 2: https://news.mit.edu/2026/ketogenic-diets-may-increase-cancer-risk-small-intestine-0715

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