A new study has found that eating French fries three or more times per week may increase the risk of developing type 2 diabetes. The findings suggest that not all potato-based foods are equal when it comes to long-term health effects.
An international group of researchers, including an expert from the University of Cambridge, examined dietary patterns and health records from more than 205,000 U.S. medical professionals. Participants were followed for nearly four decades, with repeated dietary surveys collected during that time. By the end of the study, over 22,000 cases of type 2 diabetes had been documented.
The results, published in The British Medical Journal, showed that individuals consuming French fries at least three times a week had a 20% higher risk of type 2 diabetes. In contrast, eating baked, boiled, or mashed potatoes was not associated with the same risk increase. Researchers emphasized that the preparation method, rather than the potato itself, appears to play a key role.
The study also explored whether replacing potatoes with other foods affected diabetes risk. Substituting three weekly servings of potatoes with whole grains was linked to an 8% lower risk of type 2 diabetes. However, replacing them with white rice was associated with a higher risk, highlighting the importance of nutrient quality in dietary swaps.
According to Dr. Faye Riley from Diabetes UK, type 2 diabetes is shaped by many factors, including genetics, age, and ethnicity. While diet is only one piece of the puzzle, she noted that food preparation methods matter. Choosing whole grains over fried or heavily processed foods supports a more balanced diet and may help lower the chances of developing type 2 diabetes.
Scientific References
Bhupathiraju SN, et al. Potato consumption and risk of type 2 diabetes: results from three prospective cohort studies. BMJ. 2025; [PMID: pending].
Willett WC, et al. Dietary fat and carbohydrate quality in relation to risk of type 2 diabetes mellitus. JAMA. 2002;288(14):1723–1730. [PMID: 12365956].
Hu FB. Globalization of diabetes: the role of diet, lifestyle, and genes. Diabetes Care. 2011;34(6):1249–1257. [PMID: 21617109].
Diabetes UK. Understanding type 2 diabetes. Available at: https://www.diabetes.org.uk/
[Accessed 6 September 2025].
