And a yam's no sweet potato.

If you're planning a hearty feast, choose sweet potatoes rather than yams as a side dish. Sweet potatoes are full of vitamin A in the form of beta carotene. Yams, on the other hand, have significantly less of this important nutrient. Studies suggest that beta carotene can help fight cancer and heart disease.

To get even more nutrition from your sweet potatoes, bake them in their skins and eat them whole -- just as you would a regular white potato. You'll get a healthy amount of fiber.