Potatoes and Diabetes: Understanding the Nuanced Relationship
A new Harvard study has sparked conversations about the relationship between potato consumption and diabetes risk, offering insights that go beyond simply labeling potatoes as “good” or “bad.” This research provides a more nuanced understanding of how different potato preparations affect our health, challenging us to reconsider our dietary choices in practical ways.
The comprehensive Harvard study followed over 205,000 individuals for more than three decades, carefully analyzing their dietary patterns and health outcomes. What emerged was a revelation about French fries specifically: consuming three servings weekly increased diabetes risk by 20%. However, other potato preparations like baked and mashed potatoes didn’t show the same concerning association. Lead researcher Seyed Mohammad Mousavi emphasized this shift in thinking: “We’re shifting the conversation from, ‘Are potatoes good or bad?’ to a more nuanced — and useful — question: How are they prepared, and what might we eat instead?” This distinction helps consumers make more informed choices without completely eliminating a food staple from their diets.
The research offers practical dietary substitutions that could significantly impact diabetes risk. Replacing any type of potato with whole grains reduced type 2 diabetes risk by 4%, while specifically swapping French fries for whole grains led to an impressive 19% risk reduction. Even substituting French fries with refined grains like white bread showed beneficial effects. As Professor Walter Willett, who corresponded on the study, noted: “The public health message here is simple and powerful: Small changes in our daily diet can have an important impact on the risk of type 2 diabetes.” These findings empower individuals to make incremental changes that could yield substantial health benefits over time.
This Harvard study builds upon previous research, including an Australian study that found people consuming the highest amounts of potatoes had a 9% higher diabetes risk compared to those eating the least. Importantly, the Australian research made distinctions between preparation methods, finding that boiled potatoes specifically had a “null effect” on diabetes risk. Dr. Nicola Bondonno from Edith Cowan University clarified: “It’s only fries and mashed potatoes [that increase risk], the latter likely because [they’re] usually made with butter, cream and the like.” This growing body of evidence suggests that cooking methods and added ingredients, rather than potatoes themselves, may be the primary concern.
Despite these cautions about certain preparations, potatoes offer numerous health benefits worth considering. They’re rich in antioxidants including flavonoids, carotenoids, and phenolic acids that help combat serious conditions like cancer and heart disease. While potato starch is often maligned, the resistant starch in potatoes actually feeds beneficial gut bacteria, promoting digestive health and blood sugar control. Polish researchers even discovered in 2022 that glycoalkaloids—naturally occurring chemicals found in potatoes, peppers, and goji berries—possess cancer-fighting properties. These nutritional attributes highlight why completely eliminating potatoes might deprive us of valuable nutrients.
Registered nutritionist Caroline Susie captures this balanced perspective perfectly: “Potatoes are just fantastic. What happens is, unfortunately, we tend to screw them up by not eating the skin or frying or mixing them with everything under the sun, like sour cream and butter and bacon.” This encapsulates the emerging consensus about potatoes and health—the problem isn’t inherently with potatoes themselves but with how we prepare them. By being mindful of preparation methods, portion sizes, and frequency of consumption, we can continue to enjoy potatoes as part of a balanced diet while minimizing potential health risks. Rather than viewing potatoes as forbidden foods, we might instead see them as versatile ingredients that can be incorporated into health-promoting meals when prepared thoughtfully.
