A cup of cooked squash provides anywhere from 1.2 to 6.4 grams of fiber, depending on the variety. Winter squashes like acorn and butternut pack significantly more fiber than summer squashes like zucchini. That range matters because the general recommendation for adults is about 14 grams of fiber per 1,000 calories consumed, which works out to roughly 25 to 30 grams per day for most people.
Winter Squash Has the Most Fiber
Winter squashes are the clear winners when it comes to fiber. Acorn squash leads the pack at 6.4 grams per cup (mashed), making a single serving roughly 20 to 25 percent of your daily fiber needs. That puts it on par with a cup of cooked broccoli or a medium pear.
Spaghetti squash, despite being a winter variety, is much lower at 2.2 grams per cup. Its stringy, noodle-like texture comes from a higher water content and less dense flesh compared to other winter squashes. Kabocha squash falls even lower at about 1.2 grams per two-thirds cup serving, though its small standard portion size partly explains that number.
Here’s how common varieties compare per cup of cooked squash:
- Acorn squash (mashed): 6.4 g
- Spaghetti squash: 2.2 g
- Kabocha squash (2/3 cup): 1.2 g
Summer Squash Is Lower in Fiber
Zucchini and yellow crookneck squash contain noticeably less fiber than their winter counterparts. A cup of cooked zucchini slices (with skin) has just 1.3 grams of fiber. Yellow summer squash is comparable. The difference comes down to water content: summer squashes are harvested young, when they’re tender and full of moisture. Winter squashes mature longer on the vine, developing denser, starchier flesh that concentrates more fiber per bite.
That doesn’t make summer squash a poor choice. At roughly 20 calories per cup, zucchini delivers a decent amount of fiber relative to its calorie count. It’s just not the variety to rely on if you’re specifically trying to boost fiber intake.
The Skin Makes a Difference
Leaving the skin on adds meaningful fiber. Research on spaghetti squash found that the peel contains about 2.5 grams of fiber per 100 grams of fresh weight, compared to 1.6 grams in the flesh alone. That’s roughly 57 percent more fiber, gram for gram.
This matters most for varieties with edible skins. Delicata squash has a thin skin that softens completely when roasted, so you eat the whole thing. Kabocha skin is thicker but still edible once cooked. For butternut or acorn squash, most people peel or scoop out the flesh, which means losing the skin’s extra fiber. If you’re roasting acorn squash in wedges, try eating the skin too, as it becomes tender enough at high heat.
Canned Pumpkin Is a Convenient Option
Canned pumpkin (the plain variety, not pie filling) provides about 2.9 grams of fiber per 100 grams. Because it’s a concentrated purée with less water than fresh-cooked squash, it packs fiber into a smaller volume. A half-cup serving stirs easily into oatmeal, smoothies, or yogurt, making it one of the simplest ways to add squash fiber to your diet without any prep work.
Don’t Toss the Seeds
Roasted squash seeds are a useful bonus source of fiber. One ounce of dried, hulled pumpkin and squash seed kernels (about 142 seeds) contains 1.1 grams of fiber, along with protein, magnesium, and zinc. They won’t transform your fiber intake on their own, but scattering them over salads or soups adds up over a day.
How Squash Compares to Other Vegetables
For context, a cup of cooked acorn squash at 6.4 grams of fiber outperforms many commonly recommended high-fiber foods. A cup of cooked green peas has about 9 grams, a cup of cooked Brussels sprouts about 4 grams, and a medium sweet potato about 4 grams. Zucchini’s 1.3 grams is closer to a cup of raw lettuce or cucumber in fiber terms.
If you’re choosing squash partly for its fiber, winter varieties are worth the extra cooking time. Roasting acorn or butternut squash in large batches gives you a fiber-rich side dish for several days. Pairing it with beans, whole grains, or leafy greens builds a meal that can cover a third or more of your daily fiber needs in a single sitting.