Love French fries? Your blood sugar hates them – the diabetes trap explained

Ah, French fries. The comfort food. it's crispy, salty, golden, and the solution to every bad day, we tell ourselves.

It's great, but it might just be doing a number on your health. A new study published in The BMJ has some sobering news: eating three servings of French fries a week is linked to a 20 per cent higher risk of developing type 2 diabetes.

Before you toss your fries in despair and wonder what you can really enjoy in this life, there’s a twist: eating potatoes in other ways—baked, boiled, or mashed—doesn’t carry the same risk. So it’s not the potato itself that’s the problem, it’s how we cook it, season it, and (let’s be honest) smother it in extra salt and oil.

The researchers also looked at what happens when you swap potatoes for other carbs. Replacing any potato dish with whole grains lowered diabetes risk, while swapping them for white rice actually increased it. So, your side dish choices matter, big time.

Why fries spell trouble

Potatoes are packed with nutrients: fibre, vitamin C, magnesium—all good stuff. But they’re also high in starch, giving them a high glycemic index. That means they can spike your blood sugar, especially when fried. Frying potatoes doesn’t just add fat; it changes them chemically, creating compounds that may harm your body over time.

 Most commercial fries are ultra-processed, cooked in refined oils, often rich in omega-6 fats, and sometimes reheated multiple times. This creates harmful compounds like trans fats and advanced glycation end products—fancy science terms that basically mean your fries are stressing your body’s cells, increasing inflammation, and messing with your metabolism. Toss in extra salt, coatings, flavorings, and sugars, and you’ve got a recipe for gut imbalance, water retention, high blood pressure, and eventually insulin resistance.

So yes, fries are delicious, but if you’re having them frequently, your pancreas are working overtime.

What the numbers say

The BMJ study followed over 205,000 health professionals in the U.S. from 1984 to 2021. That’s nearly 40 years of data, and during that time, 22,299 participants developed type 2 diabetes. The results? For every three weekly servings of French fries, the diabetes risk shot up by 20%. Total potato intake also increased risk, but only by 5%. Meanwhile, baked, boiled, or mashed potatoes were basically neutral—they didn’t increase risk significantly.

 Replacing just three weekly servings of fries with whole grains lowered diabetes risk by 19%, while swapping other forms of potatoes for whole grains reduced it by 4–8%. White rice, however, was not your friend: replacing potatoes with it actually raised diabetes risk.

Narjesene Rasheed, Head of Nutrition and Wellness at Kaya Clinic, breaks it down.

How to eat fries without the guilt

The good news: You don’t have to banish fries forever. You just need smarter swaps and a little creativity.

Oven-bake or air-fry: Skip deep-frying. A little olive or avocado oil goes a long way.

Sweet potato fries: Naturally sweeter, packed with fiber and beta-carotene, and easier on your blood sugar.

Veggie fries: Mix it up with carrot sticks, zucchini, beetroot, parsnip, or even asparagus. You get a crunch, color, and extra nutrients.

Portion control: Love fries? Fine. Keep the serving small and balance it with protein like grilled chicken, fish, or legumes. This helps slow sugar absorption.

Spice it up, not put salt: Use paprika, rosemary, thyme, oregano, garlic powder, or chili flakes for flavor without piling on sodium.

These small changes let you indulge your cravings without constantly spiking your blood sugar or putting your long-term health at risk.

Baked, boiled, or mashed: Potatoes aren't the enemy

 The study also reminds us that not all potatoes are bad. Baked, boiled, or mashed versions can fit into a healthy, sustainable diet—especially when combined with whole grains, veggies, and lean proteins. The key takeaway: It’s all about preparation, portions, and pairing.

 Researchers note that the study focused mainly on health professionals of European ancestry, so we need more diverse studies to fully understand the global picture. Still, the guidance aligns with current dietary recommendations: prioritise whole grains, enjoy potatoes in healthier ways, and be mindful of processed, fried foods.

You don’t have to give up fries completely to be healthy, but frequency, preparation, and portion control matter. French fries are fun, comforting, and yes, occasionally magical—but they should be treats, not staples.

 Swap them wisely, spice creatively, and keep your indulgence balanced. That way, you can still enjoy golden, crispy goodness without giving your pancreas a full-time job. Your future self (and your sweet tooth) will thank you.