People who eat three portions of French fries a week have a significantly higher risk of developing type 2 diabetes, according to new research. However, those who consume similar amounts of boiled, baked or mashed potatoes do not face an increased risk.
An international team of researchers, including an expert from the University of Cambridge, analysed data from studies tracking the health of more than 205,000 health workers in the US. The team conducted repeated surveys about people's diets over almost four decades.
Study reveals stark differences
During the follow-up periods, researchers documented some 22,000 cases of type 2 diabetes. The study found that consumption of baked, boiled or mashed potatoes were not linked to an increased risk of type 2 diabetes.
However, people who had a higher consumption of French fries faced substantially greater risks. Those eating at least three weekly servings had a 20% increased risk, whilst people consuming fries five times a week appeared to have a 27% increased risk.
Cooking method proves crucial
"The risks associated with potato intake varied by cooking method," the authors wrote in The BMJ. "The association between higher potato intake and increased T2D risk is primarily driven by intake of French fries."
The research team also discovered that replacing three servings of potatoes each week with whole grains lowered the risk of type 2 diabetes by 8%. However, replacing potatoes with white rice was associated with an increased risk.
Expert analysis supports findings
"Replacing any form of potatoes, particularly French fries, with whole grains is estimated to lower the risk of T2D, reinforcing the importance of promoting whole grains as an essential part of a healthy diet," the researchers wrote. The team also performed a review of all other studies on the topic which had similar findings.
In a linked editorial published in The BMJ, experts from the US and Denmark noted the connection to ultra-processed foods. "This finding also corresponds to the observed associations between high intake of ultra-processed foods and high risk of type 2 diabetes - French fries are often ultra-processed, whereas baked, boiled, or mashed potatoes are often minimally processed," they wrote.
UK diabetes expert weighs in
Dr Faye Riley, research communications lead at Diabetes UK, said the research shows that the link between potatoes and type 2 diabetes isn't straightforward. "Type 2 diabetes is a complex condition, with many factors influencing its development, including genetics, age and ethnicity," she said.
"Diet is just one part of the picture, but this study suggests that how food is prepared can make a difference and reinforces the advice to prioritise whole grains and cut back on fried or heavily processed foods as a way to support a balanced diet and reduce your risk," Riley added.
(PA) Note: This article has been edited with the help of Artificial Intelligence.
