Study Links French Fries to Higher Type 2 Diabetes Risk

Research indicates that consuming potatoes may increase the risk of developing type 2 diabetes, particularly when they are prepared as French fries. A study involving over 205,000 people in the United States, published in The BMJ, found that individuals who ate three servings of French fries per week had a 20 percent higher risk of this chronic condition. The findings underscore the importance of food preparation methods in dietary health.

The Harvard University-led research tracked participants’ dietary habits over more than three decades. During this period, more than 22,000 individuals were diagnosed with type 2 diabetes. The study revealed that those who consumed at least seven servings of potatoes per week faced a 12 percent increased risk of developing diabetes compared to those who rarely ate potatoes. When focusing specifically on French fries, the risk escalated significantly, rising to 27 percent for those eating seven servings weekly.

Understanding the Nutritional Impact

While potatoes are known to provide essential nutrients such as fibre, potassium, and vitamin C, they also contain substantial amounts of starch, which converts to glucose in the body. This conversion is a concern, as starches can contribute to elevated blood sugar levels when consumed in excess. The study’s lead researchers emphasized that the increased diabetes risk is primarily linked to the intake of French fries. In a statement, Diana Díaz Rizzolo, a lecturer at the Open University of Catalonia – Barcelona, noted, “In nutrition, it is not only what we eat that matters, but also what we stop eating when we do so.”

The study’s authors recommend prioritizing whole grains and limiting fried foods, even those that might seem healthy, such as potatoes. Cristóbal Morales, a specialist in endocrinology and nutrition at Vithas Sevilla Hospital in Spain, who was not involved in the study, reiterated this point. He stated that individuals should be cautious about their potato consumption and consider healthier preparation methods.

Examining the Broader Context

Despite the study’s findings, it has limitations. Participants who consumed more potatoes tended to have less active lifestyles and less nutritious diets overall, often including higher quantities of red meat, eggs, refined grains, and sugary beverages. While researchers attempted to account for these lifestyle factors, the results may still reflect skewed data.

The correlation noted in the study does not definitively prove that consuming French fries causes type 2 diabetes, merely that there is a relationship. Previous studies, including one from 2015, also observed a link between potato consumption and diabetes risk but did not differentiate between preparation methods. In 2019, an expert panel advised limiting potato intake to approximately 350 grams per week, equivalent to one large Russet potato.

Some experts argue that potatoes should not be solely blamed for health issues, as they often accompany other foods, particularly in American diets where they are paired with red or processed meats, both linked to increased diabetes risk.

The latest findings reinforce the perspective that whole foods should not be demonized without considering their preparation, accompaniments, and overall dietary context. As Díaz Rizzolo stated, “We should not demonise whole foods without considering how they are prepared, what they are accompanied by, or what they are replaced with.”

For those aiming to maintain a healthy diet, experts suggest focusing on both the cooking methods of potatoes and the alternatives presented on the plate. French fries are often ultra-processed, and such foods have been associated with negative health outcomes, while baked, boiled, or mashed potatoes are typically less processed.

In conclusion, Morales emphasized that the study delivers a clear message: adopting and maintaining healthy lifestyles and nutrition is crucial in the effort to prevent type 2 diabetes.