Should people with diabetes eat sweet potatoes?

Sweet potatoes are known to be high in fiber, contain many antioxidants, and have a low glycemic index, meaning they don't immediately impact blood sugar levels. This can help people with diabetes manage their blood sugar.

Sweet potatoes can be prepared in many ways, such as boiling, steaming, baking, or microwaving. No matter how they are eaten, this starchy vegetable provides a rich source of nutrients to supplement your diet. However, how sweet potatoes affect blood sugar levels and how to incorporate them into a balanced, healthy diet is not something everyone knows.

1. Nutritional composition of sweet potatoes

Sweet potatoes come in many varieties, including purple, yellow, white, honey, and Japanese sweet potatoes. They are rich in vitamins A, B6, and C, potassium, and fiber. However, orange sweet potatoes contain more beta-carotene, while purple sweet potatoes contain more anthocyanins. Both beta-carotene and anthocyanins are health-boosting antioxidants. A medium-sized sweet potato contains a moderate amount of refined carbohydrates, is a good source of fiber, and boasts an impressive amount of vitamins and minerals.

According to the U.S. Department of Agriculture (USDA) organic certification, a cooked sweet potato (114g) with skin on contains the following nutrients:

Calories: 103 Carbohydrate: 24g Sugar: 7g Fiber: 4g Protein: 2g Fat: 0g Sodium: 41mg Potassium: 542mg Vitamin C: 22mg Vitamin A: 1,100mcg

2. How do sweet potatoes affect blood sugar levels?

Like all foods containing carbohydrates, sweet potatoes can raise blood sugar levels. The extent of the increase depends on the total serving size, how the sweet potatoes are cooked, and what foods they are combined with.

However, according to nutrition experts, sweet potatoes should not be completely eliminated from the diet simply because they contain carbohydrates. The U.S. Centers for Disease Control and Prevention notes that there is no single correct serving size that suits everyone, so how many carbs to eat depends on individual needs. People with diabetes should consult an endocrinologist and nutritionist to determine the appropriate amount.

Like many other starchy foods, sweet potatoes are high in carbohydrates and low in protein and fat. This means they are more likely to cause a blood sugar spike if eaten alone. However, when combined with other foods containing fat and protein, this can make a difference in their impact on blood sugar levels.

3. Can people with diabetes eat sweet potatoes?

According to Dr. Megan Huff, a cardiovascular nutritionist in Atlanta, USA, people with diabetes can still eat sweet potatoes. The fiber content in sweet potatoes, especially when eaten with the skin on, can help reduce spikes in blood sugar. Additionally, how you cook sweet potatoes can also help reduce the rate of blood sugar spikes. For example, boiled sweet potatoes have a lower glycemic index than baked sweet potatoes. The glycemic index measures how quickly food can raise blood sugar levels. Therefore, foods with a low glycemic index tend to have less impact on blood sugar.

4. How should people with diabetes eat sweet potatoes?

People with diabetes should combine sweet potatoes with protein sources and non-starchy vegetables. These foods take longer to digest, thus providing "slow" energy and causing slow, stable changes in blood sugar levels.

To create a balanced meal, eat sweet potatoes with protein and fat to slow down digestion and sugar absorption. Combining sweet potatoes with protein- and fiber-rich foods can help people with diabetes better control blood sugar spikes after eating.

Foods that pair well with sweet potatoes include cheese, any protein source such as chicken, seafood, or steak, and foods that are as high in fiber as possible. Ideally, the fiber should be non-starchy vegetables, such as broccoli, leafy greens, or green beans. Additionally, adding fat to foods high in carotenoids increases their bioavailability and conversion into the active form of vitamin A, a fat-soluble vitamin.

Dr. Megan Huff recommends boiling sweet potatoes instead of baking them because boiling helps to break down starch less, according to a 2022 study published in the journal Food Chemistry.

Sweet potatoes are packed with nutrients and provide fiber-rich carbohydrates that can be a great addition to any meal, which is important for a balanced diet whether or not you have diabetes.