A new Harvard University study, published in the British Medical Journal, found that eating French fries just three times a week can raise your risk of developing type 2 diabetes by 20%. In contrast, the study showed that boiled, baked, or mashed potatoes carry no such risk. The research, led by Dr. Syed Muhammad Mousavi and co-authored by renowned nutritionist Dr. Walter Willett, analyzed over 30 years of dietary and health data from more than 250,000 participants.
The Frying Method Is the Key Issue
Researchers believe that the way potatoes are prepared is the primary factor. Frying at high temperatures in unhealthy oils creates harmful compounds, while boiling or baking preserves the potato’s nutritional value without adding trans fats. Dr. Mousavi explained, “Replacing French fries with whole grains can lower diabetes risk by up to 19%,” adding that “replacing them with another fried food won’t help.”
The American Diabetes Association also warns that fried foods, particularly French fries, often contain trans fats, which can increase the risk of heart disease and stroke. The association’s nutritionist, Stacy Krausik, advised people to “choose whole, less processed foods and use healthier cooking methods rather than frying.”
Potatoes Themselves Aren’t the Problem
Not all experts believe that potatoes deserve a negative reputation. Dr. Hanna Kahliova from the Physicians Committee for Responsible Medicine noted that boiled potatoes might even assist in weight loss and reduce the risk of diabetes. She cited studies from Iran, Finland, and the Netherlands that showed people who consumed a high amount of boiled potatoes had a 50% lower risk of diabetes.
Dr. Mousavi emphasized that public health messages should focus less on labeling foods as “good” or “bad” and more on preparation methods and healthy alternatives. The study’s findings, which included two meta-analyses covering over 500,000 people, reinforce the idea that the quality of your diet is as much about how you cook as it is about what you eat.
