For those managing diabetes, prediabetes, or weight gain, the choice between white potatoes and sweet potatoes often comes up. While sweet potatoes are commonly touted as the “healthier” option, the reality is more nuanced. Blood sugar control depends not just on the type of potato, but also on cooking method, portion size, and what you eat alongside it.
The glycaemic index (GI) measures how quickly foods raise blood sugar. White potatoes usually have a moderate to high GI, depending on variety and cooking method. Boiled white potatoes have a moderate GI, while mashed or baked potatoes spike sugar faster. Sweet potatoes typically have a lower to moderate GI, especially when boiled, making them slightly better for gradual blood sugar rise.
Fibre slows digestion and prevents rapid sugar spikes. Sweet potatoes generally contain more fibre than white potatoes, particularly if eaten with skin. They are also rich in beta-carotene, supporting overall health. White potatoes provide fibre too, but less so, and peeling reduces it further.
Per 100 grams:
White potatoes: ~17g carbs
Sweet potatoes: ~20g carbs
The calorie difference is minimal, but portion control is crucial. Eating too much of either can spike blood sugar, regardless of type.
Boiled and cooledpotatoes create resistant starch, acting like fibre and improving blood sugar response.
Fried or mashedversions spike sugar faster and add unhealthy fats.
Pair potatoes withprotein and fibreto slow digestion.
Avoid deep-frying for both white and sweet potatoes.
Sweet potatoes have a slight advantage for people with diabetes or insulin resistance because of lower GI, higher fibre, and richer micronutrient content. White potatoes are not harmful if eaten in moderate portions and cooked healthily. The key ispreparation, portion, and overall diet qualityrather than demonising one type.
