While many Thanksgiving favorites contain a lot of unhealthy ingredients, some sides are actually very healthy. Brussels sprouts are full of vitamins A and C and also have anti-inflammatory and anti-cancer properties. Try roasting your Brussels sprouts with a small amount of olive oil and balsamic vinegar. Butternut squash is packed full of essential nutrients such as calcium, magnesium, and zinc. The green beans inside of a green bean casserole are full of important vitamins and fiber. However, this dish can contain a lot of sodium as a result of the mushroom soup, soy sauce, and fried onions. Mashed potatoes contain plenty of potassium and fiber; just make sure not to use too much butter or cream cheese. Cranberry sauce can be a great source of antioxidants that help to reduce your risk of heart disease. Dieticians recommend making it from scratch as canned cranberry sauce can often contain a lot of added sugar.