A new study has found that eating French fries regularly may increase your risk of developing type 2 diabetes.
But the same risk does not apply to other types of potato dishes, such as boiled, baked, or mashed potatoes.
The study, published in The BMJ, looked at how different ways of cooking potatoes affect health, especially in relation to diabetes.
Potatoes are a popular food around the world. They are rich in important nutrients like vitamin C, fiber, and magnesium. However, they also have a lot of starch, which makes them high in glycemic index. This means they can raise blood sugar levels quickly.
In the past, this led some experts to believe that potatoes might be bad for people at risk of diabetes. But researchers wanted to take a closer look—especially at how potatoes are cooked and what people eat instead of potatoes.
To do this, scientists studied the eating habits and health data of more than 205,000 health professionals in the United States. These people took part in three large studies from 1984 to 2021. They filled out detailed food surveys every four years.
At the start, none of the participants had diabetes, heart disease, or cancer. Over almost 40 years of follow-up, more than 22,000 of them developed type 2 diabetes.
After adjusting for other lifestyle and diet habits, the researchers found that eating three servings of French fries per week was linked to a 20% higher risk of getting type 2 diabetes.
On the other hand, eating boiled, baked, or mashed potatoes in similar amounts did not raise the risk in any noticeable way. Eating three servings of any type of potato (including French fries) per week increased the risk by about 5% overall.
The researchers also explored what happens when people replace potatoes with other foods. They found that replacing three weekly servings of potatoes with whole grains, like brown rice or oats, lowered the risk of diabetes by 8%.
If people swapped French fries for whole grains, the benefit was even greater—a 19% lower risk. However, if potatoes were replaced with white rice, the risk of diabetes actually went up.
This study is observational, meaning it shows links between eating habits and health outcomes, but it does not prove that French fries directly cause diabetes. There could be other factors involved that the study did not measure. Also, most of the people in the study were white health professionals, so the results might not apply to everyone.
Still, the researchers say their findings match current health advice: whole grains should be a part of a healthy diet, and not all potatoes are equal when it comes to diabetes risk. French fries appear to be the worst option. Baked, boiled, or mashed potatoes are much better choices, especially when eaten as part of a balanced diet.
The researchers also note that potatoes are more environmentally friendly to grow compared to many other foods. That means choosing healthier forms of potatoes could be good for both your body and the planet. But they also stress the need for more studies in diverse populations, and more focus on how potatoes are cooked and what they replace in the diet.
In summary, French fries may raise your risk of diabetes, while other forms of potatoes do not. And if you want to cut your risk even further, swap potatoes for whole grains rather than white rice. It’s not just about what you eat, but also how it’s prepared and what you choose instead.
If you care about diabetes, please read studies about Scientists find a promising treatment for type 2 diabetes and findings of Certain type 2 diabetes treatment may bring heart risks.
For more about diabetes, please read studies about New type 2 diabetes treatment could help patients stop taking insulin and findings of Scientists find true cause of inflammation in type 2 diabetes.
The study is published in BMJ.
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