Nick NorwitzMD PhD, Oxford-Harvard | Metabolic Health Educator | “Stay Curious”

Debunking the Misleading Keto Cancer Study: What You Need to Know

19 Jul 2025 · 1 min

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1:10

In this video, Nick Norwitz critiques a recently published study that claimed ketogenic diets increase the risk of all cancers. He highlights several critical flaws: the study’s “most ketogenic” group still consumed about 30% of calories from carbohydrates (≈181 g/day), which is comparable to a high‑carb diet rather than a true ketogenic regimen. Norwitz explains how the authors used a proprietary “keto potential score” that mathematically equates a high‑carb intake (≈200 g/day) with a 4:1 ketogenic diet, inflating the perceived cancer risk. He also points out the study’s reliance on a retrospective two‑day food questionnaire, which provides insufficient dietary data for robust conclusions. Overall, Norwitz argues the paper’s methodology, misclassification of diets, and peer‑review process are misleading and should not be taken as evidence that keto diets cause cancer.

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Ketogenic diets are associated with elevated risk for all cancers. That's the title of a new paper that was so comically bad, it's more entertaining than alarming. Now, the first red flag was their most ketogenic quintile consumed a diet that was 30% calories from carbs. That's 181 grams of carbs per day. So yeah, their most ketogenic group was eating as many carbs as you'd find in 12 slices of white bread. And if that wasn't bad enough, using their own weird calculations and methodology, a high-carb diet with 200 grams of carbs per day can yield a keto potential score that, in terms of its cancer risk, is equivalent to a medical 4:1 ketogenic diet with 90% of calories from fat. That's not just misleading. That's turn you around 12 times, put you in a barrel, and shove you down Niagara Falls misleading. And the cherry on top, the collected data was collected using a retrospective 2-day food questionnaire. So basically they asked people what they ate for the last 2 days, found that the low-carb group was eating 181 grams of carbs per day and called it keto, then abused math to pretend keto was associated with cancer. Nice one, peer review.