Does the sweetness of sweet potatoes disqualify these colorful starchy veggies from gaining elite health status? Perhaps the name has something to do with it—it does suggest they’re sugary starch bombs! And many of the ways we prepare sweet potato recipes are certainly less than healthy. For instance, deep frying them for sweet potato fries, dousing sweet potatoes in salt, topping them with marshmallows for a dessert casserole, and dipping them in sauces like ketchup or aioli. But before you start altering them, what’s the baseline truth about sweet potato nutrition facts?
Do You Really Know What a Sweet Potato Is?
First things first, let’s get clear on what a sweet potato is and isn’t. White potatoes, sweet potatoes, and yams are often assumed to be close relatives, but that’s not the case. All three are root vegetables, and to get a little more precise, all three are tubers, which form at the base of roots and store energy to support plant growth in the form of starch.
Regular potatoes (Solanum tuberosum) belong to the nightshade family, which also includes peppers, tomatoes, and eggplants. They’re only distantly related to sweet potatoes. In most parts of the world, the term yams refer to tubers of several vine species in the Dioscorea plant genus, which are related to grasses and lilies.
In the United States and Canada, however, people often use the terms sweet potatoes and yams interchangeably, even though the two tubers are not identical and in fact are not even that closely related. Botanically speaking, sweet potatoes belong to the vine species Ipomoea batatas in the morning glory family.
For more information on the difference between sweet potatoes and yams, check out this article.
Crucial Sweet Potato Nutrition Facts
Sweet potatoes are an excellent source of a multitude of valuable nutrients, including fiber, vitamin A, vitamin C, manganese, and more.
According to the United States Department of Agriculture National Nutrient Database, one medium, uncooked sweet potato (which the USDA defines as a diameter of 2 inches, a length of 5 inches, and a weight of 114 grams) contains:
- Calories: 103
- Carbohydrates: 23.6 grams
- Protein: 2.3 grams
- Total fat: 0.2 grams
- Dietary fiber: 3.8 grams
- Vitamin A: 21,909 IU, or 438% of your daily recommended allowance (RDA)
- Vitamin C: 22.3 milligrams, or 37% of your RDA
- Manganese: 0.6 milligrams, or 28% of your RDA
- Vitamin B6: 0.3 milligrams, or 16% of your RDA
- Potassium: 541 milligrams, or 15% of your RDA
- Pantothenic acid: 1 milligram, or 10% of your RDA
Sweet potatoes also contain some copper, niacin, thiamine, magnesium, riboflavin, phosphorus, vitamin E, vitamin K, calcium, and iron.
As you can see, the nutritional value of sweet potatoes is high, with plenty of vitamins, minerals, and other phytonutrients your body needs to meet its daily values and maintain optimal health.
The Health Benefits of Sweet Potatoes
All tubers—again, depending on how you cook them—can absolutely be a part of a healthy, balanced diet. But sweet potatoes have a bit of a leg up in the health benefits category.
For one thing, there’s their color, which is due to beta carotene, one of a group of red, orange, and yellow pigments known as carotenoids. A cup of sweet potatoes provides 375% of your daily recommended beta-carotene intake!
Beta-carotene is a precursor to vitamin A, a potent antioxidant that protects your skin from sun damage among other desirable effects, including strengthening eye health. According to one study, sweet potatoes have the potential to be “food-based supplements” used to treat vitamin A deficiency.
Sweet potatoes are also high in vitamin C and other antioxidants that help protect against free radical damage and strengthen the immune system. Purple sweet potatoes are especially high in protective antioxidants called anthocyanins.
Sweet potatoes also, despite their name, have an even lower glycemic index (GI) score than non-sweet, regular potatoes. The glycemic index measures how foods affect your blood sugar levels. Foods with lower GI scores are digested more slowly, meaning you avoid blood sugar spikes and drops that can mess with your energy levels and leave you feeling hangry, even for people with type 2 diabetes.
So, while a “normal” baked potato, for example, has a GI of 111 and a boiled potato has a GI of 2, a baked sweet potato weighs in at 86.5 and a boiled sweet potato at 46.
Then there are the boons for heart health. Rich in potassium, sweet potatoes help improve blood pressure by ushering excess sodium and fluid out of the body. Potassium also helps protect against the risk of heart disease by regulating muscle contractions and heart rhythm.
A Quick Note About Sweet Potato Carbs
While there may not be as many calories in sweet potatoes as you thought, the same can’t be said about sweet potato carbs. One reason people eating paleo love sweet potatoes so much is that they’re a terrific source of energizing, filling carbohydrates.
This doesn’t detract from how nutrient dense and healthy sweet potatoes are, but it does mean that if you’re adhering to a low-carb diet like the ketogenic diet, they may not be the best choice for you. With 23.6 grams of carbohydrates per medium-sized sweet potato, if you’re eating a low-carb diet and do want to include sweet potatoes, you’ll definitely need to be conscientious of portion size.