Squash is my go-to winter vegetable... my six favorites that ease digestion, keep you full and ward off the flu: JOHANNAH KATZ

When it comes to the healthiest winter squash, you might expect butternut or pumpkin to take the top spot. But many of their often-overlooked cousins have a surprisingly impressive nutritional profile. From bright orange butternut to pasta-like spaghetti squash, winter squashes offer a wide variety of vitamins, minerals, fiber and healthy plant compounds.And as flu season gets underway, they may even have protective antioxidants that could ward off pesky winter bugs. As a registered dietitian, I'm constantly recommending my patients add more squash to their sheet-pan dinners, curries, bowls and pastas. While there is no single healthiest squash for everyone, certain varieties stand out for my clients and on my grocery list. Below, I have ranked six of my favorites based on their nutritional strengths, versatility and benefits for different health goals. Squash is packed with vital nutrients that immune, heart and digestive health 6. Delicata Squash: Best for Easy PreparationDelicata squash earns its place on this list because sometimes the healthiest vegetable is the one you'll 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 also makes it particularly appealing to people who aren't usually excited about eating their vegetables.My favorite way to eat it is simple: slice it into half moons, toss with olive oil and roast until golden. Add to salads or serve alongside salmon or chicken - no peeling required.5. Spaghetti Squash: The lower-carb pasta alternative Spaghetti squash can serve as a replacement for traditional pasta. Consider pairing it with lean protein for added balanceSpaghetti 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 - or simply add more vegetables to comforting fall meals. 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, so what you serve with it matters when rounding out a meal. Adding chicken, turkey, shrimp, tofu or beans can make it more balanced.And you don’t have to give up pasta altogether. Mixing spaghetti squash with regular spaghetti is another easy way to increase your vegetable intake and get used to the differences in texture and taste.I like to roast the squash halves until tender and then use a fork to separate the strands. Toss with marinara, sautéed vegetables and your favorite protein for a lighter take on spaghetti.4. Kabocha Squash: The little-known veggie with eye-supporting vitaminsSometimes 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 plant pigments, also found in carrots and sweet potatoes, include beta-carotene, which the body converts into vitamin A, lutein and zeaxanthin.These nutrients are concentrated in the retina and help support low-light vision and protect against degeneration.A recent study published in HortScience found that certain kabocha varieties contained substantial amounts of carotenoids, although exact amounts varied depending on the variety, maturity and storage conditions. Kabocha also provides fiber and carbohydrates, making it a satisfying side dish, particularly when paired with a source of protein.Consider cutting it into wedges and roasting with olive oil and a little salt. Like delicata, the skin also softens when cooked and can be eaten.3. Pumpkin: Affordable and flu-fighting canned staple When shopping for canned pumpkin, choose plain varieties to avoid excess amounts of added sugarPumpkin might be the most recognizable winter squash, and it isn’t just good for making pies.Like butternut squash, pumpkin gets its orange color from beta-carotene, which the body converts into vitamin A to support vision, as well as immune and skin health.Vitamin A helps maintain protective mucosal barriers in the respiratory and digestive tracks, the body's first line of defense against the flu and common cold. It also comes in a can, which can be far cheaper and more shelf stable than fresh produce. One cup of plain canned pumpkin contains about 83 calories, 7g of fiber and 500mg 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 and is incredibly versatile, making it great for both sweet and savory recipes.Stir plain pumpkin puree into oatmeal, blend it into smoothies or add it to soups, chilis and sauces for extra fiber and nutrients. Just make sure to choose 100 percent pumpkin puree and not pumpkin pie filling to cut down on added sugar.2. Butternut squash: Best for vitamin A and immune Health Butternut squash can easily be blended into a soup or cubed with olive oil, cinnamon and rosemaryButternut 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 7g of fiber and about 580mg of potassium. Butternut squash also provides about 34 percent of the daily recommended value of vitamin C, which helps produce disease-fighting white blood cells and reduces inflammation during infections.That's an impressive nutritional package for relatively few calories. The fiber supports digestion and fullness, and potassium plays an important role in maintaining healthy blood pressure.Butternut squash has a naturally sweet, slightly nutty flavor, making it an appealing way to add more vegetables to meals, even for picky eaters.Consider roasting cubed butternut squash with olive oil, cinnamon and rosemary, then add it to grain bowls or salads. It also blends nicely into creamy soups without needing much cream.1. Acorn squash: Packed with fiber and heart-healthy compounds One cup of baked acorn squash contains more than twice the potassium of a medium banana, which supports heart healthAcorn squash takes my top spot thanks to its impressive fiber and potassium content, making it a standout choice for digestive and heart health. One cup of baked acorn squash contains around 9g of fiber and nearly 900mg of potassium. For perspective, that's about one-third of the recommended 28g daily fiber intake and more than twice the amount of potassium in a medium banana.Fiber supports digestion and regular bowel movements, helps lower cholesterol and promotes fullness, while potassium helps counteract sodium's effects on blood pressure. Acorn squash also provides about 21 percent of the daily value for magnesium and 24 percent for vitamin B6 in just one cup. Both support important functions such as muscle health and energy metabolism. Johannah Katz (pictured) is a registered dietitian who frequently recommends winter squash to her patientsAcorn squash contains more carbs than some other winter varieties, but those carbs come packaged with fiber and beneficial nutrients.I like to slice acorn squash in half, scoop out the seeds and roast it until tender. Then, stuff the center with quinoa, lentils, vegetables or ground turkey for a balanced and delicious meal.So which one is the healthiest? The answer depends on your nutritional goals and preferences.Acorn squash takes the top spot for its high fiber and potassium content, while butternut stands out for vitamin A and other essential nutrients. Kabocha offers an impressive range of carotenoids, and canned pumpkin is 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 attention to portions.Ultimately, I wouldn't choose just one favorite. 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.Johannah Katz, MA, RD, is a registered dietitian based in Florida.