The potato has been questioned for years. Is it healthy or bad for you? New research suggests the real problem may not be the potato itself, but how we cook it.
Scientists at Harvard studied over 205,000 American health professionals for about thirty years. During this time, 22,299 participants developed type 2 diabetes, a disease where the body cannot control blood sugar properly. The results were published in The BMJ journal.
When researchers examined how potatoes were prepared, they found something interesting. Eating French fries three times a week increased the risk of type 2 diabetes by 20%. However, baked, boiled and mashed potatoes showed no real connection to the disease. The same vegetable produced completely different health outcomes depending on how it was cooked.
Led by Seyed Mohammad Mousavi and professor Walter C. Willett, the team asked an important question: what if people ate different foods instead of fries?
The answer was surprising. Replacing three weekly servings of French fries with whole grains reduced the diabetes risk by about 19%. Even replacing baked potatoes with whole grains helped a little. However, replacing potatoes with white rice actually increased diabetes risk.
To confirm these findings, researchers combined their data with 12 other studies from around the world, involving 587,000 people and 43,000 diabetes cases. The pattern remained the same.
The study tracked real behavior over time rather than conducting controlled experiments, so it cannot prove that fries directly cause diabetes. Whole grains, which raise blood sugar slowly, proved most beneficial. The research suggests the problem is not the potato, but what happens in the deep fryer.