Johannah Katz's Top 6 Winter Squashes to Boost Immunity

Squash stands as my primary choice for winter eating. These six varieties ease digestion, keep you feeling full, and help fight off the flu. Johannah Katz, a registered dietitian, shares her top picks. Many people expect butternut or pumpkin to lead the pack. However, their often-overlooked cousins offer surprisingly impressive nutritional profiles. From bright orange butternut to pasta-like spaghetti squash, winter squashes provide vitamins, minerals, fiber and healthy plant compounds. As flu season begins, they may even possess protective antioxidants that could ward off pesky winter bugs.

I constantly recommend my patients add more squash to sheet-pan dinners, curries, bowls and pastas. There is no single healthiest squash for everyone. Certain varieties stand out for clients and on grocery lists. Below, I have ranked six favorites based on nutritional strengths, versatility and benefits for different health goals. Squash is packed with vital nutrients that support immune, heart and digestive health.

Delicata squash earns its place because sometimes the healthiest vegetable is the one you will actually make and eat. Unlike butternut squash, which usually needs peeling, delicata has thin, edible skin that softens when cooked. That means less prep time and less food waste. Delicata also contains fiber and potassium, which support digestion, fullness and healthy muscle function. Its slightly sweet, nutty flavor makes it appealing to people who aren't usually excited about eating vegetables. My favorite way to eat it is simple: slice into half moons, toss with olive oil and roast until golden. Add to salads or serve alongside salmon or chicken without peeling required.

Spaghetti squash serves as a replacement for traditional pasta. Consider pairing it with lean protein for added balance. Spaghetti squash has a unique advantage. When cooked, its flesh separates into thin strands resembling noodles. That makes it a practical option for people looking to cut calories or carbohydrates. One cup of plain cooked spaghetti squash has about 42 calories, 10g of carbohydrates and 2g of fiber. For comparison, a cup of cooked traditional pasta generally contains around 200 calories and more than 40g of carbs. Despite the name, spaghetti squash isn't nutritionally equivalent to pasta. What you serve with it matters when rounding out a meal. Adding chicken, turkey, shrimp, tofu or beans can make it more balanced. You don't have to give up pasta altogether. Mixing spaghetti squash with regular spaghetti is another easy way to increase vegetable intake and get used to differences in texture and taste. I like to roast the squash halves until tender then use a fork to separate strands. Toss with marinara, sautéed vegetables and your favorite protein for a lighter take on spaghetti.

Kabocha squash is the little-known veggie with eye-supporting vitamins. Sometimes called Japanese pumpkin, kabocha has a dense, creamy texture and a naturally sweet flavor similar to a sweet potato. Its standout nutritional feature is its carotenoid content. These compounds are essential for maintaining good vision while you enjoy the comfort of fall flavors. Each variety brings something unique to your plate without unnecessary waste or effort.

Acorn squash takes the top spot because it packs a serious punch for your digestion and heart. One cup of baked acorn holds around 9 grams of fiber, which aids regular bowel movements and helps lower cholesterol. It also offers nearly 900 milligrams of potassium. That amount is more than twice what you find in a medium banana. Fiber keeps you full, while potassium works to counteract the blood-pressure-raising effects of sodium. Just one cup delivers about 21 percent of your daily magnesium needs and 24 percent of vitamin B6.

These plant pigments are also found in carrots and sweet potatoes. They include beta-carotene, which the body converts into vitamin A, plus lutein and zeaxanthin. These nutrients concentrate in the retina to support low-light vision and guard against degeneration. A recent study published in HortScience showed that certain kabocha varieties held substantial amounts of carotenoids. Exact levels varied depending on the variety, maturity, and storage conditions. Kabocha also provides fiber and carbohydrates, making it a satisfying side dish when paired with protein. Try cutting wedges and roasting them with olive oil and salt. Like delicata squash, the skin softens during cooking and is safe to eat.

When shopping for canned pumpkin, choose plain varieties to avoid excess added sugar. Pumpkin might be the most recognizable winter squash, but it isn't just good for pies. Like butternut squash, pumpkin gets its orange color from beta-carotene. This converts into vitamin A to support vision, immune function, and skin health. Vitamin A helps maintain protective mucosal barriers in the respiratory and digestive tracts. These barriers act as the body's first line of defense against the flu and common cold. It also comes in a can, which is far cheaper and more shelf stable than fresh produce.

Pumpkin remains affordable and serves as a flu-fighting canned staple. One cup of plain canned pumpkin contains about 83 calories, 7 grams of fiber, and 500 milligrams of potassium. It also provides immune-boosting iron and vitamin C. Unlike many winter squashes that require peeling, chopping, and roasting, canned pumpkin is ready to use straight from the pantry. Its versatility makes it great for both sweet and savory recipes. Stir plain puree into oatmeal, blend it into smoothies, or add it to soups and chilis. Just make sure you choose 100 percent pumpkin puree and not pumpkin pie filling to cut down on sugar.

Butternut squash is particularly rich in beta-carotene, the pigment responsible for its bright orange color. One cup of baked butternut squash contains about 82 calories, nearly 7 grams of fiber, and roughly 580 milligrams of potassium. It also provides about 34 percent of the daily recommended value of vitamin C. This vitamin helps produce disease-fighting white blood cells and reduces inflammation during infections. That is an impressive nutritional package for relatively few calories. The fiber supports digestion and fullness, while potassium plays an important role in maintaining healthy blood pressure. Its naturally sweet, slightly nutty flavor makes it appealing even to picky eaters. Consider roasting cubed butternut squash with olive oil, cinnamon, and rosemary. Add it to grain bowls or salads, or blend it into creamy soups without needing much cream.

These winter vegetables offer a clear path toward better health through simple dietary choices. Acorn squash leads the list for heart-healthy compounds, while pumpkin offers an affordable way to boost immunity during flu season. Butternut squash bridges the gap with its rich vitamin A content and manageable cooking process. Communities facing food insecurity might find canned pumpkin especially valuable due to its low cost and long shelf life. Choosing these varieties helps lower cholesterol and supports blood pressure without demanding complex preparation methods. The facts speak for themselves: more fiber, less sodium reliance, and better nutrient density are the goals.

Both acorn squash and butternut squash support critical body functions like muscle health and energy metabolism. Johannah Katz, a registered dietitian based in Florida, frequently recommends winter squash to her patients for these very reasons. She often slices acorn squash in half, scoops out the seeds, and roasts it until tender. Then she stuffs the center with quinoa, lentils, vegetables, or ground turkey to create a balanced meal. Acorn squash contains more carbs than some other winter varieties, but those carbohydrates come packaged with fiber and beneficial nutrients. So which one is actually the healthiest? The answer depends entirely on your specific nutritional goals and personal preferences. Acorn squash takes the top spot for its high fiber and potassium content. Butternut stands out for vitamin A and other essential nutrients. Kabocha offers an impressive range of carotenoids, while canned pumpkin serves as an affordable, convenient source of beta-carotene. For lighter, lower-carbohydrate meals, spaghetti squash is a great option, and delicata makes prep quick and easy. Some winter squash varieties are particularly rich in potassium, so people with kidney disease who need to limit potassium should pay careful attention to portions. Johannah Katz notes that she would never choose just one favorite variety for her diet plan. Diversifying the winter squashes you eat is a great way to enjoy a wider range of nutrients, flavors and textures while making healthy eating more interesting and enjoyable. This approach helps communities build better habits without risking nutrient deficiencies or excesses.