Managing blood sugar levels is crucial for people with diabetes, especially when it comes to carbohydrate-rich foods like potatoes. Potatoes are a staple in many diets but are known to cause rapid spikes in blood glucose due to their high glycemic index (GI). However, the way potatoes are prepared and consumed can affect their impact on blood sugar. One common question is whether eating leftover potatoes is better or worse for diabetics compared to freshly cooked ones.





How potatoes affect blood sugar

Potatoes are high in starch, which the body breaks down into glucose, causing blood sugar to rise. For diabetics, whose insulin response may be impaired, these blood sugar surges can be harmful. Freshly cooked potatoes tend to have a higher glycemic index, meaning they cause quicker and greater blood sugar spikes.





What happens when potatoes are leftover?

When potatoes are cooked and then cooled (leftover), their starch transforms into "resistant starch. According to a study published in National Library of medicine it was found that " Resistant starch behaves like fiber in the digestive system, slowing down digestion and glucose absorption. This slower digestion results in a lower and more gradual rise in blood sugar levels compared to freshly cooked potatoes.”








Benefits of resistant starch in leftover potatoes for diabetics

The resistant starch in cooled or leftover potatoes can improve insulin sensitivity and reduce post-meal blood sugar spikes, making them potentially better for diabetics. Eating potato salad made from boiled and cooled potatoes is often recommended as a more diabetes-friendly way to enjoy this vegetable.



Things to keep in mind

Despite these benefits, the portion size and preparation method matter. Deep-fried potatoes like French fries should be avoided due to added fats, which can negatively affect heart health and insulin resistance. Small portions of cooled boiled potatoes combined with fiber or healthy fats (such as in a salad with vegetables and yogurt) are preferable.