For many years, potatoes have had a mixed reputation when it comes to health.
Some people see them as a nutritious and affordable food, while others believe they contribute to weight gain and chronic diseases.
Potatoes are one of the most widely eaten foods in the world and appear in many forms, including French fries, baked potatoes, mashed potatoes, and boiled potatoes.
However, a major new study suggests that not all potato dishes affect health in the same way.
Researchers have found that French fries may carry a much greater risk for type 2 diabetes than potatoes prepared using other cooking methods.
The findings come from a large study published in The BMJ, one of the world’s leading medical journals.
Type 2 diabetes is a growing global health problem. It develops when the body becomes less effective at using insulin, a hormone that helps regulate blood sugar.
Over time, blood sugar levels can rise to unhealthy levels, increasing the risk of heart disease, kidney disease, vision problems, nerve damage, and other serious complications.
Because diet plays a major role in diabetes risk, scientists have spent many years studying foods that may increase or decrease the likelihood of developing the condition.
Potatoes have often attracted attention because they contain large amounts of starch, which is quickly broken down into glucose in the body. Foods that cause blood sugar to rise rapidly are often considered less favorable for long-term metabolic health.
However, researchers noted that previous studies often treated all potatoes as a single food group.
In reality, there is a major difference between a boiled potato and a serving of French fries. The way food is prepared can change its nutritional profile and its effects on the body.
To better understand these differences, researchers analyzed data from more than 205,000 health professionals in the United States. Participants were followed for nearly four decades. During the study, more than 22,000 people developed type 2 diabetes.
The researchers found that eating three servings of French fries per week was associated with a 20% higher risk of developing type 2 diabetes. In contrast, eating baked, boiled, or mashed potatoes was not linked to a significant increase in risk.
The study also examined replacement foods. Replacing potatoes with whole grains such as oats, brown rice, barley, and whole wheat products was linked to a lower risk of diabetes. Replacing French fries with whole grains was associated with a 19% lower risk.
The findings were very different when potatoes were replaced with white rice. In that case, diabetes risk increased. This shows that the foods people choose instead of potatoes can be just as important as the potatoes themselves.
The researchers emphasized that potatoes contain valuable nutrients including vitamin C, potassium, magnesium, and fiber. Potatoes can still fit into a healthy eating pattern when prepared in healthier ways.
This was an observational study, meaning it cannot prove that French fries directly cause diabetes. Other factors may also contribute. However, the very large number of participants and the long follow-up period make the findings important.
Overall, the study suggests that French fries deserve special attention when discussing diabetes risk. Other potato dishes appear much less concerning.
The findings support current dietary advice that encourages people to eat more whole grains and fewer highly processed foods. From a practical perspective, choosing baked, boiled, or mashed potatoes more often and limiting French fries may be a simple step toward better long-term health.
Looking at the evidence, the study is strong because of its size and long duration. However, more research involving different populations is still needed.
The results do not mean people must avoid potatoes completely. Instead, they suggest that cooking methods and food substitutions play a major role in determining health effects.
If you care about diabetes, please read studies about 5 vitamins that may prevent complication in diabetes, and how to manage high blood pressure and diabetes with healthy foods.
For more health information, please see recent studies about vitamin D and type2 diabetes, and to people with type 2 diabetes, some fruits are better than others.
Source: Harvard T.H. Chan School of Public Health.
