Sweet potatoes have earned a place on many plates permanently, and it’s not hard to understand why. They’re sweet, extremely versatile, and loaded with nutrients. But if you have diabetes, you may be wondering if this popular root vegetable is aiding or detracting from your blood sugar. The good news? Sweet potatoes can fit into a diabetes diet—you just have to watch what you do to them.
Why Sweet Potatoes Should Have a Place on Your Plate
From a nutritional standpoint, sweet potatoes are a powerhouse. When compared to white potatoes, they provide more vitamins, fiber, and antioxidants. They’re particularly high in vitamin A (in the form of beta-carotene), vitamin C, potassium, and vitamin B6. That fiber load is a big plus—it makes you feel fuller longer, aids digestion, and slows the transit time of carbs, which can be beneficial for blood sugar management.
Sweet potatoes, according to registered dietitian Sylvia White, also have anti-inflammatory compounds and antioxidants that can potentially reduce the risk of chronic diseases such as heart disease, which is a typical problem for those with diabetes.
Blood Sugar and the Glycemic Index: What You Need to Know
Similar to all starchy vegetables, sweet potatoes do have carbohydrates, so they will spike your blood sugar to a certain extent. But how you prepare them is crucial.
The glycemic index, or GI, is a measure of how fast a food increases blood sugar levels. Boiled sweet potatoes are more slowly digested and thus have a lower GI compared to baked, roasted, or mashed ones. To illustrate, boiled sweet potato is low to moderate on the GI scale, whereas baked sweet potato is higher.
It’s also useful to look at the glycemic load (GL), which takes into account the quality and quantity of carbohydrates. Eating in moderation helps keep your overall glycemic load manageable.
Not All Sweet Potatoes Are Created Equal
Sweet potatoes are available in several different varieties, and each has distinct advantages:
- Orange-flesh sweet potatoes: Rich in beta-carotene, excellent for eye health and immune function.
- Purple sweet potatoes: Rich in anthocyanins, a family of powerful antioxidants that can potentially quell inflammation and enhance blood sugar control.
- White-flesh sweet potatoes: Slightly less fiber but still fiber-rich and filling.
Regardless of color, all sweet potatoes can be included in an overall healthy diet if eaten in moderation.
How You Prepare Them Matters
How you prepare sweet potatoes has a significant impact on how your body will react:
- Boiling retains more resistant starch, slowing down digestion and preventing a surge in blood sugar.
- Leaving the skin intact adds even more fiber.
- Baking, roasting, or frying, conversely, dismantles more of the starch, so sweet potatoes become faster to digest and more likely to spike your blood sugar.
Missing sweet potato fries? Best to have them as an occasional treat, not as a frequent side dish.
Keep Portions Under Control
Portion size is crucial when living with diabetes. The American Diabetes Association suggests that starchy foods such as sweet potatoes occupy no more than one-fourth of your plate—that’s about half a small sweet potato or about half a cup.
Combining sweet potatoes with lean proteins (such as chicken, fish, tofu, or eggs) and non-starchy vegetables (such as spinach, broccoli, or zucchini) helps stabilize blood sugar even better.
Smarter Toppings, Better Results
Ditch sugary toppings such as marshmallows or brown sugar. Substitute with healthier, more delicious alternatives such as:
- A spoonful of plain Greek yogurt
- A light sprinkle of cinnamon
- A dollop of nut butter
- A dash of ginger or turmeric
Or get creative—mash sweet potatoes with spice, blend them into smoothies, or top sweet potato toast with cottage cheese or a poached egg.
Sweet potatoes aren’t forbidden if you have diabetes—instead, they can be a tasty and healthy addition to your diet. If you pick the right kind, prepare them in ways that work for diabetes, and use moderate portion sizes, you can reap all the health benefits they have without causing a blood sugar spike. With a little prep, sweet potatoes can go from a holiday favorite to a healthy, daily staple.