Butternut squash, a type of winter squash known for its creamy texture and mild, sweet flavor, is a popular vegetable used in soups, side dishes, and purees. A standard one-cup serving of cooked, cubed butternut squash contains approximately 21.5 grams of total carbohydrates. This content contributes the majority of its 82 calories per serving, making understanding its precise composition important for dietary planning.
The Core Answer: Carbohydrate Breakdown
A single cup of cooked butternut squash contains 21.5 grams of total carbohydrates, which is the sum of its fiber, sugars, and starches. This total breaks down into two main categories: digestible and indigestible carbohydrates. The indigestible portion comes from dietary fiber, which accounts for a substantial 6.6 grams of the total carbohydrate count in that same serving.
The presence of this high fiber content allows the squash to be classified as a lower “net carb” food. Net carbs are calculated by subtracting the grams of dietary fiber from the total grams of carbohydrates, since fiber is not fully digested and does not raise blood sugar in the same way as other carbs. For a cup of cooked butternut squash, the net carbohydrate count is approximately 14.9 grams (21.5 grams total carbs minus 6.6 grams of fiber).
The remaining digestible carbohydrates include natural sugars, which contribute about 4 grams to the total in a one-cup serving. These sugars, primarily sucrose and fructose, are responsible for the vegetable’s inherent sweetness, especially after it is cooked or roasted. The majority of the remaining net carbohydrates are complex starches, which are digested slowly and contribute to the feeling of fullness.
Glycemic Index and Glycemic Load
The way butternut squash affects blood sugar levels is measured by its Glycemic Index (GI) and Glycemic Load (GL) values. The Glycemic Index is a scale that ranks carbohydrate-containing foods based on how quickly and how high they raise blood glucose levels. Plain, cooked butternut squash has a moderate GI of about 51, which is considered low to moderate on the scale.
While the GI provides a measure of quality, the Glycemic Load offers a better real-world picture because it factors in the typical serving size. The GL calculation multiplies the food’s GI by the amount of digestible carbohydrates in a serving, then divides by 100. Due to its high fiber and water content, butternut squash has a very low Glycemic Load, typically ranging from 3 to 6 per serving.
This low Glycemic Load indicates that the quantity in a standard portion has only a minimal impact on blood sugar levels. Foods with a GL of 10 or less are generally considered to have a low impact, making butternut squash a suitable carbohydrate choice for managing stable blood sugar.
Comparison to Other Starchy Vegetables
Butternut squash’s carbohydrate profile is notably lower compared to other commonly consumed starchy vegetables. A one-cup serving of baked sweet potato, for instance, typically contains a much higher total carbohydrate count, often ranging between 41 and 58 grams. This is nearly double the carbohydrate content found in the same volume of cooked butternut squash.
The difference is also apparent in the sugar content; sweet potatoes can contain as much as 13 to 19 grams of sugar per cup, significantly more than the 4 grams found in butternut squash. When comparing on a per-weight basis, such as 100 grams, cooked butternut squash contains approximately 42% fewer carbohydrates than a russet potato. This makes butternut squash a lower-carbohydrate alternative to traditional root vegetables, while still providing complex carbohydrates and fiber.