Sweet and regular potatoes are both tuberous root vegetables, but they differ in appearance and taste.
They come from separate plant families, offer different nutrients, and affect your blood sugar differently.
This article describes the main differences between sweet potatoes and other potato varieties, plus how to prepare them in healthy ways.
Different plant families
Sweet and regular potatoes are both considered root vegetables but are only distantly related.
Sweet potatoes are from the morning glory family, Convolvulaceae, and white potatoes are nightshades, or Solanaceae. The edible part of these plants are the tubers that grow on the roots.
Both varieties are native to parts of Central and South America but now eaten all over the world.
Sweet potatoes typically have brown skin and orange flesh but also come in purple, yellow, and red varieties. Regular potatoes come in shades of brown, yellow, and red and have white or yellow flesh.
In the United States and some other countries, sweet potatoes are often called yams, even though they’re different species.
Sweet and regular potatoes are both root vegetables. They’re distantly related but come from different families.
Both are nutritious
Sweet potatoes are often touted as being healthier than white potatoes, but in reality, both types can be highly nutritious.
Here’s a nutrient comparison of 3.5 ounces (100 grams) of white and sweet potato with skin, respectively:
While regular and sweet potatoes are comparable in their calorie, protein, and carb content, white potatoes provide more potassium, whereas sweet potatoes are incredibly high in vitamin A.
Both types of potatoes also contain other beneficial plant compounds.
Sweet potatoes, including red and purple varieties, are rich in antioxidants that help fight cell damage in your body caused by free radicals.
Regular potatoes contain compounds called glycoalkaloids, which have been shown to have anticancer and other beneficial effects in test-tube studies.
Both types of potatoes are rich in fiber, carbs, and vitamins B6 and C. White potatoes are higher in potassium, whereas sweet potatoes contain more vitamin A.
Different glycemic indexes
Different types of potatoes also differ in their glycemic index (GI), a measure of how a certain food affects your blood sugar.
Foods with a GI of 70 or higher cause a more rapid increase in blood sugar compared with foods with a medium GI of 56–69 or a low GI of 55 or less.
Depending on the type and cooking process, sweet potatoes may have a GI of 44–94. Baked sweet potatoes tend to have a much higher GI than boiled ones because of how the starches gelatinize during cooking.
The GI of regular potatoes also varies. For example, boiled red potatoes have a GI of 89 while baked Russet potatoes have a GI of 111.
People who have diabetes or other blood sugar issues may benefit from limiting high-GI foods. Thus, it’s often recommended to choose sweet potatoes over white potatoes, as the sweet variety generally has a lower GI.
However, how eating potato affects your blood sugar largely depends on the type of potato, portion size, and cooking method. While some varieties of sweet potatoes may have a lower GI than regular potatoes, others do not.
The effect that eating potato has on your blood sugar, known as the GI, varies among different types of both sweet and regular potatoes.
Both can fit into a balanced diet
Both sweet and regular potatoes provide fiber, vitamins, minerals, and energizing carbs and can fit into a balanced diet that includes a variety of other healthy foods.
How to prepare them in healthy ways
Though potatoes are highly nutritious, they’re often prepared in unhealthy ways.
For example, white potatoes can be turned into French fries, mashed with butter and cream, or baked and topped with high-calorie ingredients.
What’s more, sweet potatoes may be combined with sugar, marshmallows, or other less healthy ingredients.
To prepare sweet or regular potatoes in a healthy way, try boiling or baking them, keep the skin on for more fiber, and serve with fresh herbs or spices instead of cheese, butter, and salt.
If you’re concerned about the impact of these root vegetables on your blood sugar, opt for boiled over baked potatoes.
Pairing potatoes with foods that have fewer carbs, like lean proteins and non-starchy vegetables, can also limit their effect on blood sugar.
Both sweet and regular potatoes can be part of a balanced diet. Bake or boil potatoes instead of frying them, and stick to nutritious toppings.