Butternut Squash Glycemic Index
Low GI · The honest verdict
Gentle on blood sugar
Glycemic index
51
per source
Glycemic load
8
Low GL
This food's glycemic index is 51, which is Low GI.
Butternut squash is a starchy vegetable with a GI around 51 (low side of medium) and a low-to-moderate glycemic load per cup. Its substantial fiber and exceptional vitamin A make it more nutritious than refined starch alternatives. This is general nutrition information, not medical advice; people with diabetes should account for its carb content and confirm portions with their care team.
GI numbers vary by source, ripeness, and how a food is prepared. This is general nutrition information — not medical advice. If you manage diabetes, confirm specifics with your care team.
Key facts
One cup of cooked butternut squash provides over 1,100 mcg RAE of vitamin A — more than 100% of the adult daily recommended intake from a single vegetable serving.
Butternut squash is a starchy vegetable, not a non-starchy one — it contains approximately 22 g of carbohydrates per cooked cup, similar to sweet potato.
Mashing or pureeing starchy vegetables raises their effective GI by breaking down fiber structure and making starch more rapidly digestible.
What's actually inside
Per 100 g, with your typical serving noted as 1 cup cooked, cubed (205 g). The carb family is what moves blood sugar — fiber is the number that softens the spike.
Total carbs
21.5g
Net carbs
17.9g
total carbs minus fiber
Fiber
6.6g
slows the glucose rise
- Sugars
- 4.1g
- Protein
- 1.8g
- Calories
- 82kcal
Notable nutrients
- Vitamin A (beta-carotene)1144 mcg RAE
- Vitamin C31 mg
- Magnesium59 mg
- Potassium582 mg
- Folate39 mcg
Is it a smart choice for blood sugar?
GI is only half the story — portion (glycemic load) and what you eat it with decide the real-world effect. Here's the honest read.
The verdict
Manageable as a starchy vegetable side — portion and cooking method matter
Butternut squash is a starchy vegetable with a GI around 51 (low side of medium) and a low-to-moderate glycemic load per cup. Its substantial fiber and exceptional vitamin A make it more nutritious than refined starch alternatives. This is general nutrition information, not medical advice; people with diabetes should account for its carb content and confirm portions with their care team.
Portion guidance
One cooked cup (about 205 g) sits at a GL of roughly 8 — in the low GL range (under 10). A larger portion of 1.5 to 2 cups can push GL into medium territory (11+). Roasted or baked butternut squash has a similar glycemic response to boiled, but mashing it slightly raises the effective GI by breaking down cell structure. Pair with lean protein and healthy fat to moderate the blood sugar response.
This is general nutrition information, not personal medical advice. Blood sugar responses are individual — if you have diabetes or prediabetes, your care team can tell you how this fits your plan.
How to keep the spike small
The same food can land differently depending on how it's cooked and what it's eaten with. Use these levers to your advantage.
Roasting vs. boiling
Raises GIRoasting butternut squash caramelizes its natural sugars and can raise the effective GI compared to steaming or boiling. The effect is moderate — roasting may push GI from ~51 toward the low 60s — but the flavor difference is significant, so for a meaningful blood sugar reduction, steaming or boiling is preferable.
Mashing or pureeing
Raises GIMashing breaks down cell walls and fiber structure, making starch more rapidly digestible. Butternut squash soup or puree will have a faster glucose response than cubed cooked squash.
Eating with the skin (where applicable)
Lowers the spikeButternut squash skin is technically edible when roasted, though most people peel it. Leaving skin on adds a small amount of additional fiber, which modestly slows glucose absorption.
Pairing with protein or fat
Lowers the spikeServing butternut squash alongside chicken, fish, beans, or a drizzle of olive oil introduces protein and fat that slow gastric emptying and blunt the glucose curve of the meal.
Pairing tip
Roasted butternut squash cubes work well alongside grilled salmon or chicken — the protein and fat in the protein counterbalance the squash's moderate carb content. Avoid serving large portions as the sole carbohydrate in a meal; instead treat it as one of several vegetables. Adding olive oil and rosemary before roasting not only improves flavor but also introduces fat that moderates the glycemic response.
Why GI numbers vary
Butternut squash has a reasonably well-established GI of around 51, placing it at the lower end of the medium-GI range (56–69) — or, by some references, at the very top of the low-GI range (≤55). The University of Sydney database and comparable references cite values between 48 and 55 for cooked butternut squash. We use a GI of 51 as the best single estimate, while acknowledging that cooking method (roasting vs. boiling) and ripeness can shift the actual value by several points in either direction.
Not medical advice. This page is general nutrition information about Butternut Squash. It isn't a diagnosis or a treatment plan. If you have diabetes, prediabetes, or another condition affecting blood sugar, confirm any dietary decisions with your doctor or care team.
❓Frequently Asked Questions
Butternut squash has a glycemic index of approximately 51, which sits right at the boundary between low-GI (≤55) and medium-GI (56–69). It is classified as low-GI based on published references, but it is clearly a starchy vegetable with meaningful carbohydrate content — not a free-for-all like leafy greens. A one-cup cooked serving has a glycemic load of roughly 8, which remains in the low GL range.
In moderate portions, yes. Butternut squash is a starchy vegetable with real carbohydrate content (~22 g per cooked cup), but it is also exceptionally rich in fiber, vitamin A, potassium, and magnesium. At a one-cup serving, the glycemic load is low to moderate and manageable for most people. Larger portions, mashed preparations, or eating it as the primary carbohydrate at a meal requires more attention. People with diabetes should factor in the roughly 18 g of net carbs per cup and confirm portions with their care team.
Yes. Butternut squash is a starchy vegetable, not a non-starchy one. Non-starchy vegetables (leafy greens, peppers, cucumbers, zucchini) typically have under 5 g of net carbs per serving. Butternut squash has about 18 g of net carbs per cooked cup, putting it in the same category as sweet potato, corn, and parsnip for carbohydrate management purposes.
Yes, modestly — more than non-starchy vegetables, but significantly less than white potato or refined grain products. Its GI of ~51 and GL of ~8 per cooked cup mean a normal serving produces a gradual, moderate blood sugar rise rather than a sharp spike. Cooking method matters: mashed or pureed butternut squash raises blood sugar faster than cubed roasted or steamed.
Butternut squash and sweet potato are broadly comparable as starchy vegetables. Sweet potato has a GI ranging from 44 to 94 depending heavily on cooking method — boiled sweet potato is lower (GI ~44–46) while baked sweet potato can reach GI 90+. Butternut squash at GI ~51 boiled or roasted is generally in a similar range to boiled sweet potato and is more GI-stable across cooking methods. Both are nutritious starchy vegetables to enjoy in measured portions.
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Reviewed by
Curex Editorial TeamReviewed for accuracy
Last reviewed July 2026