Researchers have reported that eating French fries three times a week may raise the risk of developing type 2 diabetes by 20 per cent, while boiled, baked, or mashed potatoes do not appear to have the same effect.
The findings, published in The British Medical Journal (BMJ), are drawn from an analysis of more than 205,000 health professionals followed for nearly 40 years. According to the study, 22,299 cases of type 2 diabetes were recorded during this period.
After adjusting for lifestyle and dietary factors, the researchers said that for every three weekly servings of French fries, the rate of type 2 diabetes increased by 20 per cent. However, similar amounts of baked, boiled, or mashed potatoes were not linked to a substantially increased risk.
They further explained that while potatoes contain nutrients such as fiber, vitamin C, and magnesium, they also have a high starch content and glycemic index, which have previously been associated with diabetes risk. The researchers noted that preparation methods and food substitutions are critical in evaluating the overall health impact of potatoes.
The study also found that replacing three weekly servings of total potatoes with whole grains was linked to an eight per cent reduction in diabetes risk. Replacing French fries specifically with whole grains was associated with a 19 per cent lower rate, while substituting potatoes with white rice was linked to a higher risk.
Despite the large dataset, the researchers cautioned that the study was observational and could not establish cause and effect, adding that other unmeasured factors may have influenced the results.
They also acknowledged that most participants were health professionals of European ancestry, which may limit how widely the findings apply.
The researchers concluded that the link between potato consumption and type 2 diabetes risk largely depends on the foods they are replaced with. They added that their findings support existing dietary advice, which emphasizes the inclusion of whole grains in a balanced diet to help prevent type 2 diabetes.
In a linked editorial, experts emphasised that the impact of potatoes on health depends on the preparation method and what foods they replace.
They observed that boiled, baked, or mashed potatoes, when compared with French fries, could be part of a healthy and sustainable diet, especially given their relatively low environmental impact. However, they maintained that whole grains should remain a dietary priority and called for further studies in more diverse populationss.
