Foods · Carbs in food
Carbs in sweet potato, and is it good for diabetics?
How many carbs are in a sweet potato, why boiled and baked ones hit blood sugar differently, and how to fit one into a meal.
Carbs in sweet potato
| Portion | Carbs | Fiber | Net carbs | Sugar | Calories |
|---|---|---|---|---|---|
| Medium sweet potato114 g | 24 g | 4 g | 20 g | 7 g | 103 |
| Small sweet potato60 g | 12 g | 2 g | 10 g | 4 g | 54 |
| Large sweet potato180 g | 37 g | 6 g | 31 g | 12 g | 162 |
| 1 cup, mashed200 g | 41 g | 7 g | 35 g | 13 g | 180 |
Per 100 g: 20.7 g carbs, 3.3 g fiber, 2 g protein, 0.1 g fat, 90 calories. Source: USDA FoodData Central (Sweet potato, cooked, baked in skin, flesh, without salt). Net carbs = carbs minus fiber. Brands and recipes vary, so check the label when you have one.
The short version
- A medium baked sweet potato (114 g) has about 24 g of carbs, with 4 g of fiber. A large one has about 37 g.
- Yes, people with diabetes can eat sweet potato. Treat it as a starchy carb, like rice or bread, not as a free vegetable.
- Boiled raises blood sugar more slowly than baked or roasted. Cooking method matters as much as the potato.
- Keep the portion to about the size of your fist and eat it with protein and other vegetables.
How many carbs are in a sweet potato?
Size is what changes the number. USDA data for baked sweet potato (flesh, eaten without salt) gives 20.7 g of carbs per 100 g. That works out to:
- Small (60 g): about 12 g of carbs
- Medium (114 g): about 24 g of carbs
- Large (180 g): about 37 g of carbs
- 1 cup mashed (200 g): about 41 g of carbs
Supermarket sweet potatoes are often bigger than USDA's "large". A sweet potato that fills your hand from wrist to fingertips can weigh 300 g or more, which is over 60 g of carbs. If you count carbs closely, weigh it once after cooking. Boiled sweet potato has a little less per 100 g (17.7 g), because it takes on water.
About 4 g of a medium potato's carbs are fiber. If your care team has you count net carbs, that brings a medium one to about 20 g. New to counting? Our carb counting guide covers labels, portions and fiber.
Is sweet potato good for diabetics?
It can be a good choice. Sweet potato gives you fiber, vitamin A and potassium, and it is a whole food rather than a processed one. But it is still a starchy carbohydrate. Per 100 g, baked sweet potato and baked white potato are almost the same in carbs (20.7 g and 21.6 g). The sweet one just has more fiber.
So the useful question isn't "can I eat it?" but "how much, and how is it cooked?" The American Diabetes Association doesn't put any single food off limits. It points to the total carbs in a meal and the quality of those carbs, and sweet potato does well on quality.
What sweet potato does to blood sugar
Cooking changes how fast its starch turns into glucose. In a study of ten sweet potato varieties, boiled sweet potato had a glycemic index of around 40 to 50, which counts as low to medium. Baked and roasted sweet potato came out much higher, around 80 to 90, which is as fast as white bread. Baking for a long time breaks the starch down into sugars that are absorbed quickly.
In practice, many people see a faster, higher rise after a baked or roasted sweet potato than after the same weight boiled. The amount still matters most: a small baked sweet potato can raise you less than a huge boiled one.
The best test is your own meter or CGM. Check before you eat and again about 2 hours after you start. Our guide to blood sugar 2 hours after eating explains what the number means and the common targets.
How to eat sweet potato with diabetes
- Keep the portion small. Half a large sweet potato, or one small to medium one, is a sensible serving for most meals.
- Boil or steam it more often than you bake it. Leftover sweet potato eaten cold or reheated also tends to raise blood sugar more slowly than freshly cooked.
- Eat the skin. It adds fiber. Scrub it well before cooking.
- Pair it with protein and vegetables. Chicken, fish, eggs or beans plus a salad or green vegetables slow the rise compared with sweet potato on its own.
- Skip the sugary toppings. Marshmallows, brown sugar and maple syrup can add 20 g of carbs or more. Try olive oil, cinnamon, Greek yogurt or a little butter instead.
- Watch sweet potato fries. They're usually fried and served in big portions, so the carbs and fat add up quickly.
Counting it without a scale
Most of the time you won't weigh your food. In T1dApp you can take a photo of your plate and get the carbs for each food on it, including the sweet potato, shown as a range you can edit. Two hours later the app asks for your reading, so you learn how sweet potato, cooked your way, actually affects you.
Snap your meal, see the carbs
T1dApp gives you carbs, calories, protein and fat from a photo, and your likely blood sugar 2 hours later.
Sources
- USDA FoodData Central: Sweet potato, cooked, baked in skin, flesh, without salt (FDC ID 168483)
- USDA FoodData Central: Sweet potato, cooked, boiled, without skin (FDC ID 168484)
- USDA FoodData Central: Potatoes, baked, flesh, without salt (FDC ID 170033)
- Bahado-Singh PS, et al. Relationship between processing method and the glycemic indices of ten sweet potato cultivars. Journal of Nutrition and Metabolism, 2011
- American Diabetes Association. Nutrition Therapy for Adults With Diabetes or Prediabetes: A Consensus Report (2019)
This article is general information, not medical advice. Your targets, doses and diet should be set with your doctor or diabetes care team.