Are sweet potatoes healthy?

Sweet potatoes can be roasted, mashed, fried and pied – you might have eaten them so often that they feel old hat.

In a way, they are – sweet potatoes count among the world’s oldest domesticated crops. Archeological evidence suggests they were cultivated in South America “more than 4,500 years ago”, says Michelle Johnson, a seed historian, journalist and self-described “sweet potato superfan”.

Flavorful, productive, resilient and adaptable to a wide range of climates, the entire Ipomoea batatas plant is edible, and has thousands of cultivars; about 20 are sold commercially in the US, says Johnson. Surprisingly, they are kin to morning glories but unrelated to either white potatoes or yams.

Their health bona fides, however, are clear. Here’s what to know about adding more sweet potatoes to your diet.

What is the nutritional profile of sweet potatoes?

A medium orange sweet potato (about 140g, or one serving, cooked) contains about 130 calories, 30g of carbohydrates and 2g of protein. Most of the carbs come from complex starches, or slow-digesting chains of glucose molecules; less than half derive from their approximately 10g of simple sugar.

How you prepare a sweet potato can affect sugar content and glycemic index, or the speed at which a food causes blood sugar to rise. Steamed or boiled sweet potatoes retain most of their resistant starch, making them a lower GI food, while roasting sweet potatoes at high heat converts more of their starch into a sugar called maltose, giving them a higher glycemic index.

How do sweet potatoes affect blood sugar?

Despite their sugar content, sweet potatoes are still a healthy carb option for people with diabetes, says Asako Miyashita, a New York-based registered dietitian with a special focus on Japanese dietetics. That’s largely due to their high fiber content – about 4-6g per serving. Their fiber content “helps stabilize your blood sugar, as well as lower your cholesterol and increase satiety”, says Miyashita.

She advises clients to eat sweet potatoes skin-on for maximum fiber and, if diabetic, stick to servings of about half a cup paired with green vegetables and protein for ideal blood sugar balance. Cooking sweet potatoes, then cooling them and eating them later allows for the development of even more resistant starch, which behaves like fiber and helps prevent blood sugar spikes.

What digestive benefits do sweet potatoes offer?

Fiber supports good gut bacteria and helps keep you regular, but sweet potatoes offer another digestive benefit, too. Cut a raw one open and you’ll see white sap oozing out. “That contains a compound called yarapin,” Miyashita says. Yarapin aids digestion by supporting peristalsis – the muscle contractions that move food through your digestive tract.

Do sweet potatoes contain essential micronutrients?

Sweet potatoes’ micronutrient density sets them apart from other staple starches such as white potatoes, wheat and rice. A medium sweet potato will give you some manganese, iron, vitamins C and B6, and calcium, plus 12% of your daily potassium and 34% of your daily copper needs.

“Copper benefits skin, it protects against oxidative stress, and it’s important for the brain and nervous system as well,” says Sharniquia White, a North Carolina-based chef and registered dietitian. A 2025 observational study examining the effects of dietary copper on cognitive function found people with a high copper intake performed better on cognitive function tests.

Do different colored sweet potatoes have different nutritional profiles?

Orange varieties, like jewels or Beauregards, carry significant amounts of beta-carotene. The body processes beta-carotene into vitamin A and is good for our skin, hair and eyes. “It’s also really great for immune function,” says White. Beta-carotene is fat-soluble, so pairing sweet potatoes with fatty ingredients like olive oil or, as Miyashita prefers, sesame seeds can help with absorption.

Purple sweet potatoes, such as the Japanese Okinawa variety, are high in anthocyanins – antioxidants that researchers believe help combat age-related disease. Laboratory tests measuring antioxidant strength found purple sweet potato anthocyanins outperformed those from red cabbage, grapes and elderberries in fighting free radicals that contribute to cell damage. While more studies are needed, purple sweet potatoes offer “promising antitumor properties,” researchers have noted.

White sweet potatoes, like the Hannah variety, may boast fewer antioxidants than their colorful counterparts, but still offer some beta-carotene and more micronutrients and fiber than white potatoes like Idahos or russets. Even so, the takeaway isn’t to completely abandon white potatoes for sweet: “There’s a place for both” in a balanced diet, says White.

How should you choose and prepare a sweet potato?

White recommends selecting firm sweet potatoes with smooth, even skin and no smell. A sweet scent may mean the sugars are breaking down and your tuber is going bad, she says. Store them in a cool, dry place.

Sweet potatoes are popular, but people often underestimate just how much can be done with them. Lately, White has been blending cooked sweet potatoes into smoothies and adding them to chai lattes as a kind of pumpkin spice analog. She also scores thick slices of sweet potato and grills them like steak, or roasts them until cooked but firm, to use as a base for avocado “toast”.

A teacher recently sparked a TikTok trend by sharing her favorite way to eat a sweet potato: baked whole and stuffed with a baton of cheese.

“You can have them savory, you can have them sweet, you can have them for a snack, you can have them for entree,” says White. “Not only are they nutritious – they’re also very versatile.”