CAMBRIDGE, August 5, 2025 — A large international study has found that how you prepare potatoes could significantly influence your risk of developing type 2 diabetes.
Researchers analysing decades of health data from over 205,000 US healthcare professionals discovered that fried potatoes – particularly French fries – were linked to a substantially higher risk of the condition.
The increased risk was not seen in people who consumed boiled, baked or mashed potatoes, highlighting the role of added fats and high-heat cooking in diabetes development. The researchers found that eating French fries three or more times per week was associated with a 20% higher risk of type 2 diabetes.
The study, published in The BMJ, also examined food substitutions. Replacing three weekly servings of potatoes with whole grains was linked to an 8% reduction in risk, while substituting with white rice was associated with an increase.
The authors emphasised the importance of considering not just the types of food in one’s diet, but also how they are prepared. The findings support public health guidance encouraging the reduction of fried and ultra-processed foods in favour of whole, minimally processed alternatives.