Acorn Squash: USDA Nutrition, How to Cook It and Comparisons

Acorn squash is a small, ribbed winter squash with dark green skin, often with an orange patch, and sweet, mild orange flesh. One cup of baked acorn squash has about 115 calories, 9 grams of fiber (32% of the Daily Value) and roughly a fifth of the Daily Value for potassium and magnesium in USDA data. One thing surprises people: despite its orange flesh, acorn squash lists far less vitamin A than butternut squash or sweet potato. Below are the USDA acorn squash nutrition facts, how to cook acorn squash in the oven, microwave or pot, and how it compares with other winter vegetables.

Peptide Labs does not sell acorn squash or acorn squash products. This article is general nutrition information, not medical advice.

What is acorn squash?

Acorn squash gets its name from its shape: round at the top, pointed at the bottom, with deep ribs running down the sides. Botanically it is Cucurbita pepo, the same species as zucchini and many summer squashes; plant research papers describe a common variety as acorn squash ‘Table Queen’. Unlike summer squash, it is harvested mature, with a hard rind and firm flesh, which is why it keeps for weeks in a cool pantry.

In the Dietary Guidelines for Americans 2020-2025, winter squash such as acorn, butternut, kabocha and pumpkin is grouped with the red and orange vegetables, alongside carrots and sweet potatoes, not in the starchy group with potatoes and corn. Our guide to which vegetables count as starchy explains how those subgroups work.

Acorn squash nutrition per cup

The table uses three USDA FoodData Central SR Legacy entries, each at USDA’s own cup weight, with the percent Daily Value (%DV) based on the FDA Daily Values used on Nutrition Facts labels. Baked squash loses water in the oven, so a cup of baked cubes is denser than a cup of raw cubes. SR Legacy lists no sugar value for acorn squash, so sugar is left out.

Three things stand out. First, fiber: 9 grams per cup of baked squash is a lot for a vegetable, which is why winter squash shows up in our guide to fiber-rich foods; if you are not used to much fiber, add it gradually and drink fluids. Second, minerals: a cup of baked acorn squash gives about a fifth of the Daily Value for potassium and for magnesium, two nutrients covered in our guides to potassium in foods and magnesium in foods. If a clinician has told you to limit potassium, ask how winter squash fits. Third, it is a meaningful source of thiamin and vitamin B6, which few people think about when they pick a side dish.

Acorn squash is mostly carbohydrate with very little fat or protein. At about 30 grams of carbohydrate per baked cup it sits between watery vegetables and potatoes, so it is usually left off strict lists of low carb foods, while still being lower in calories per cup than sweet potato.

How acorn squash compares with other orange vegetables

Orange flesh does not always mean a lot of vitamin A. The table compares USDA cooked values per cup.

In USDA data, acorn squash brings more fiber and more potassium per cup than butternut, while butternut supplies well over a full day’s Daily Value for vitamin A, mostly as carotenoids such as those in our beta-carotene guide. Sweet potato is higher in calories and carbohydrate per cup and very high in vitamin A, as our sweet potato guide shows. Compared with boiled potato, acorn squash has about three times the fiber per cup in these entries. None of these is a better or worse choice on its own; they simply bring different strengths, and rotating them gives more variety. For another orange vegetable rich in vitamin A, see our carrots guide, and for a root vegetable with a similar role at the table, our sibling guide to rutabaga.

How to cook acorn squash

The hardest part of how to cook acorn squash is cutting it. The rind is tough and the ribs make it roll, so set it on a damp towel, slice off a thin piece to make a flat base, and use a heavy, sharp knife with steady pressure. Microwaving the whole squash for a couple of minutes first softens the rind and makes cutting easier; pierce it with a fork before you do.

• Roasted halves: cut in half from stem to tip, scoop out the seeds and stringy pulp, brush the cut side with a little oil and roast cut side down until a fork slides easily into the thickest part. Flip and season, or fill the cavity with grains, beans or vegetables.
• Roasted slices: cut the halves into crescents along the ribs and roast on a sheet pan. Thinner pieces cook faster and caramelize at the edges.
• Microwave: place halves cut side down in a dish with a splash of water, cover loosely and cook until tender. This is the quickest method for a weeknight side.
• Steamed or boiled: peeled cubes can be steamed or simmered and mashed. In USDA data, boiled mashed squash holds more water per cup, so it has fewer calories and less fiber per cup than baked cubes.
• Skin and seeds: the skin softens with roasting, and many people eat it with the flesh. The seeds can be cleaned, dried and roasted like pumpkin seeds; our pumpkin seeds guide covers that close relative.
• Flavor pairings: acorn squash is mild and slightly nutty, so it works with savory seasonings such as garlic, sage and black pepper as well as with sweet toppings. Brown sugar, maple syrup and butter add calories and sugar quickly, so taste first and add less than a recipe suggests.

To pick one, choose a squash that feels heavy for its size, with a dull, firm rind and no soft spots or cracks. Whole squash stores well in a cool, dry place; once cut, wrap it and refrigerate it, and keep cooked squash in the fridge in a covered container.

Bitter squash: the one safety note

Plants in the gourd family can make cucurbitacins, intensely bitter compounds that discourage insects and animals from eating them. Supermarket squash normally tastes mild or sweet, but occasionally a squash, especially a home-grown one, turns out strongly bitter. A 2020 case report described a 66-year-old woman admitted to an emergency department with vomiting, diarrhea and inflamed colon after eating bitter zucchini, the same species as acorn squash; she recovered with fluids, and the authors noted that the bitter taste is the key warning sign. A 2022 case report titled this kind of event toxic squash syndrome. If a bite of squash tastes unusually bitter, spit it out, throw the whole squash away and do not try to cook the bitterness out. Severe vomiting or diarrhea after eating bitter squash needs medical care.

Squash is not one of the nine major food allergens that US labels must declare. If you are eating smaller portions on a GLP-1 medicine, our GLP-1 diet guide covers how fiber-rich vegetables fit in, and our guide to daily fiber intake explains the reference values.

Frequently Asked Questions

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Last reviewed October 2026.

Related guides: Rutabaga: What It Is, USDA Nutrition and Rutabaga vs Turnip, Butternut Squash: Nutrition Facts, Vitamin A and Is It Healthy?, Starchy Vegetables: List, USDA Nutrition and Non-Starchy Swaps.