Acorn squash is a popular starchy vegetable typically found in grocery stores during the fall and winter.
It has a nutty, sweet taste and a soft, buttery texture when cooked, making it a great choice for salads, side dishes, and pureed soups.
Not only is acorn squash delicious, but it’s also a great source of nutrients. Keep reading to learn more about acorn squash nutrition!
Acorn squash provides 115 calories in each 1-cup (205-gram) serving (1).
Compared to other winter squash varieties, such as butternut and spaghetti squash, acorn squash is slightly higher in calories (2, 3).
However, acorn squash has about 50% fewer calories than sweet potatoes and white potatoes (4, 5).
+ Slightly higher in calories than other winter squash.
+ Roughly half the calories of potatoes and sweet potatoes.
Acorn squash is moderately high in carbohydrates and fiber while providing very little protein and almost no fat.
Here’s the macronutrient breakdown for 1 cup (205 grams) of cooked acorn squash (1):
- Carbohydrates: 30 grams
- Fiber: 9 grams
- Protein: 2 grams
- Fat: <1 gram
As you can see, acorn squash is exceptionally high in fiber, providing 32% of the Daily Value (DV) in each 1-cup serving.
Other starchy vegetables have much less fiber. For example, butternut squash has 6.5 grams (23% DV) and sweet potatoes have 5 grams (18% DV) of fiber per cup (3, 4).
+ High in carbohydrates.
+ Nearly 1/3 of daily fiber needs in 1 cooked cup.
+ Low in protein and fat.
A 1-cup (205-gram) serving of cooked acorn squash provides the following vitamins and minerals (1):
- Thiamin: 0.34 mg (28% DV)
- Vitamin C: 22 mg (25% DV)
- Vitamin B6: 0.4 mg (24% DV)
- Manganese: 0.5 mg (22% DV)
- Magnesium: 88 mg (21% DV)
- Copper: 0.18 mg (20% DV)
- Pantothenic acid: 1 mg (20% DV)
- Potassium: 896 mg (19% DV)
- Niacin: 1.8 mg (11% DV)
- Iron: 1.9 mg (11% DV)
- Folate: 39 mcg (10% DV)
- Phosphorus: 92 mg (7% DV)
- Vitamin A: 43 mcg RAE (5% DV)
- Zinc: 0.4 mg (4% DV)
- Selenium: 1.4 mcg (3% DV)
- Riboflavin: 0.03 mg (2% DV)
- Calcium: 0.2 mg (<1% DV)
- Sodium: 8 mg (<1% DV)
Acorn squash is an excellent source of many nutrients, including vitamin C, copper, manganese, magnesium, and several B vitamins, and is naturally low in sodium (6).
+ Excellent source of vitamins B1 (thiamin), B5 (pantothenic acid), B6, and C and the minerals manganese, magnesium, and copper.
+ Good source of vitamins B2 (niacin) and B9 (folate) and the minerals potassium and iron.
Carotenoids in acorn squash
Like most winter squash, acorn squash is a rich source of carotenoids, a group of plant pigments that give vegetables their bright red, orange, and yellow colors.
Carotenoids have strong antioxidant properties, meaning that they help protect against free radicals — compounds that have been linked to diabetes, heart disease, and cancer (7, 8).
A one-cup (140-gram) portion of raw acorn squash contains the following carotenoids (9):
- Beta-carotene: 0.31 mg
- Lutein + zeaxanthin: 0.053 mg
Acorn squash contains less beta-carotene but more lutein and zeaxanthin than similar vegetables, such as sweet potatoes and butternut squash (10, 11, 12).
For example, raw butternut squash contains almost 20 times more beta-carotene per cup than acorn squash (5.9 mg vs 0.3 mg, respectively.)
On the other hand, acorn squash provides a small amount of lutein & zeaxanthin (0.053 mg), while sweet potatoes and butternut squash don’t contain any.
There is no official recommendation for carotenoid intake, but some experts suggest getting at least 4 mg of beta-carotene, 0.6 mg of alpha-carotene, and 3.3 mg of lutein daily for general health and reduced risk of lung cancer (13).
+ Contains carotenoids, but not as much as other winter squashes.
Does cooking impact the nutrition of acorn squash?
Cooking can increase or decrease certain vitamins and minerals in acorn squash, depending on the method used.
While we didn’t find any studies on acorn squash specifically, research in similar vegetables, such as sweet potatoes, shows how some nutrients are affected by cooking (14, 15):
- Beta-carotene: increases by up to 30% when boiled and decreases by up to 20% when steamed or microwaved
- Vitamin C: decreases by up to 50% with any cooking method
- Polyphenols: increase by up to 45% with any cooking method
- Antioxidant capacity: increases by up to 320% with any cooking method
Beta-carotene and other carotenoids increase with some cooking methods because heat breaks down the cell walls in vegetables, allowing it to be released and more easily absorbed (16).
For most other nutrients, boiling is the method that reduces nutrient content the most. To retain more minerals and water-soluble vitamins, try microwaving, steaming, or baking instead (17, 18).
+ Try baking or steaming, instead of boiling, to preserve minerals and water-soluble vitamins.
+ Cooking increases polyphenol and antioxidant availability (compared to raw).
Acorn squash is an incredibly nutritious variety of winter squash, providing a generous amount of fiber, vitamin C, B vitamins, manganese, and magnesium.
It also contains carotenoids — plant pigments with strong antioxidant properties that can help protect against chronic diseases like cancer, heart disease, and age-related macular degeneration (13).
Acorn squash is an excellent way to add variety to your diet and boost your overall health. Enjoy it in a variety of dishes for a nutritious meal!
Amy Richter is a Registered Dietitian Nutritionist based in Missouri. She is an experienced nutrition writer and medical advisor for Healthline and Medical News Today. Amy is passionate about all things food-related and enjoys translating complex science into easy-to-understand articles.