Eating French Fries Linked to 20% Higher Risk of Type 2 Diabetes. A new Harvard University study published in the British Medical Journal found that eating French fries just three times a week can raise the risk of developing type 2 diabetes by 20%. In contrast, boiled, baked, or mashed potatoes carry no such risk, highlighting the importance of cooking methods in health outcomes.
French Fries & Diabetes Risk
The research was led by Dr. Syed Muhammad Mousavi and nutritionist Dr. Walter Willett. They analyzed more than 30 years of data from over 250,000 people. Their findings show that frying potatoes, especially at high temperatures in unhealthy oils, creates harmful compounds that increase diabetes risk.
“Replacing French fries with whole grains can lower diabetes risk by up to 19%,” said Dr. Mousavi. “Swapping fries for another fried food won’t help.”
Why Frying Makes a Difference
How you cook potatoes changes their nutritional impact. Frying introduces trans fats, increases carbohydrates, and forms harmful chemicals. In contrast, boiling or baking keeps nutrients intact and avoids added fats or flour-based coatings.
Fried Foods Have Other Health Risks
The American Diabetes Association warns that fried foods—especially French fries—can also raise the risk of heart disease and stroke. Many fries are coated with flour or breading, which adds extra carbs.
Nutritionist Stacy Krausik advises choosing whole, less processed foods. She recommends using healthier cooking methods, such as baking or steaming.
Potatoes Are Not the Enemy
Experts agree that potatoes themselves are not unhealthy. According to Dr. Hanna Kahliova from the Physicians Committee for Responsible Medicine, boiled potatoes may help reduce diabetes risk and even support weight loss. She referred to studies from Iran, Finland, and the Netherlands, where people who ate more boiled potatoes had over 50% lower risk of type 2 diabetes.
A Better Public Health Approach
Dr. Mousavi said that public health messages should not label foods as “good” or “bad.” Instead, people need education about how food is prepared and how to make healthier swaps.
The study also included two meta-analyses, covering over 500,000 individuals and 43,000 diabetes cases. The results confirm that how you cook your food matters as much as what you eat.
