Researchers at the Harvard T.H. Chan School of Public Health found that eating just three servings of french fries per week was associated with a 20% higher risk of developing T2D. Baked, boiled or mashed potatoes, however, were not linked to an increased risk.

And replacing those three French fry orders with whole grains — for example, whole grain pastas or bread — cut the odds of type 2 diabetes by up to 19%, the Harvard team found. Even subbing refined (not whole) grains for French fries helped lower diabetes risk.

French fries, but not mashed, baked or boiled potatoes, were linked to type 2 diabetes in a new study whose authors say food preparation makes a difference.