Overview
- A BMJ analysis published in early June 2026 found that eating three servings of French fries per week was associated with about a 20% higher rate of type 2 diabetes.
- The study pooled repeated diet data from more than 205,000 U.S. health professionals across three long-running cohorts and recorded 22,299 new diabetes cases during follow-up.
- Eating three weekly servings of boiled, baked, or mashed potatoes showed no statistically significant link to diabetes, while replacing potatoes with whole grains was linked to lower diabetes rates and replacing them with white rice was linked to higher rates.
- Researchers point to higher calorie density of fries, weight gain as a likely mediating pathway, and compounds formed during high‑temperature frying as possible mechanisms but say these do not prove cause and effect.
- The evidence is observational, the sample is mostly U.S. health professionals of European ancestry, and authors call for more diverse and mechanistic studies before changing policy, though they note the results support limiting fried and ultra‑processed foods.