Sweet news for yam fans: Carbohydrates can be good for you—as long as they’re complex carbohydrates, like those found in sweet potatoes.

Complex carbohydrates contain the best possible fuel for your body, said Lynda Fanning, a registered dietitian with the Virginia Dietetic Association.

“Thankfully, sweet potatoes, which many people call yams, are available year-round,” Fanning added.

Grown all over Virginia, they come in different colors of skin and flesh: white, yellow, orange, pink and even deep purple.

According to the George Mateljan Foundation, a nonprofit organization that provides information about why the world’s healthiest foods are key ingredients in good health, there are close to 400 varieties of sweet potatoes.

The differing shades of the sweet spuds reflect the presence of potent health promoters called phytochemicals, Fanning explained. For example, the common orange sweet potato is chock-full of the antioxidant beta carotene, and it’s important to get nutrients like that from whole foods rather than from vitamins.

Based on U.S. Department of Agriculture guidelines, Americans should have an average of nine servings of fruits and veggies each day. Those help fight against some cancers, heart disease, stroke and diabetes, Fanning said.

“Sweet potatoes can be your first line of defense, because they are nutritional all-stars. Most people think of broccoli or apples as the nutritional stars, and they are great,” she said.
But of all vegetables, sweet potatoes were ranked No. 1 in nutrition by the Center for Science in the Public Interest. Sweet potatoes were given a score of 184, outscoring the next-highest vegetable in the ranking by more than 100 points.

Points were given for dietary fiber, naturally occurring sugars and complex carbohydrates, protein, vitamins A and C, iron and calcium. Points were deducted for fat content, sodium, cholesterol, added refined sugars and caffeine. The higher the score, the more nutritious the food.

Sweet potatoes have almost twice the recommended daily allowance of vitamin A, 42 percent of the recommendation for vitamin C, four times the amount of daily beta carotene and, when eaten with the skin, more fiber than oatmeal.

If you have high blood pressure, it helps to know that these tubers are also strong in potassium, Fanning said. And if you have diabetes, sweet potatoes have a lower glycemic index, which means they are slower to affect blood sugar.

The sweet potato is native to Central America and is one of the oldest vegetables known to man. They began to be cultivated by Americans in the 16th century, and the orange-fleshed version was introduced to the United States in the mid-20th century, according to the Mateljan Foundation.

Today sweet potatoes are often enjoyed as part of a traditional Thanksgiving feast, but they are starting to join the mainstream of American meals and people are eating sweet potatoes more often—roasted, mashed, baked and fried.

“They are melt-in-your-mouth delicious,” Fanning said. “Baked whole with a touch of butter and a tiny drizzle of maple syrup, they will beat any dessert for taste, and surpass it in nutrients as well.”
She suggested making sweet potato baked fries by cutting the potatoes into strips, tossing them in a bowl with just enough canola oil to lightly coat the fries, then baking them until tender.
“Find a source of locally grown sweet potatoes for maximum flavor and nutrients,” Fanning added.