What Happens to Your Body When You Eat Japanese Sweet Potatoes Regularly

Japanese sweet potatoes are slightly nutty, subtly sweet tubers packed with fiber, antioxidants, and vitamins A and C. Eating them regularly may support gut health, blood sugar, and heart health.

1. They’re Packed With Nutrients

“Japanese sweet potatoes are a nutrient-dense, healthy food, and have a similar nutrition profile to classic orange sweet potatoes,” said Amy Davis, RDN, a registered dietitian nutritionist in Downey, California.

They’re also loaded with micronutrients. A serving offers over 100% of your daily vitamin A needs, about 40 percent of your daily vitamin C, potassium, and beneficial antioxidants.

According to Davis, one medium Japanese sweet potato provides: 

• 100 calories
• 24 grams of carbs
• 4 grams of fiber
• 7 grams of sugar
• 2 grams of protein

2. They Support Gut Health

The fiber in Japanese sweet potatoes can help keep your digestive system moving smoothly, said Sharniquia White, MS, RDN, LDN, a chef and registered dietitian nutritionist in Greensboro, North Carolina.

Fiber adds bulk to stool, supports regular bowel movements, and helps prevent constipation. It’s also a prebiotic, which means it feeds the beneficial bacteria in your gut so they can thrive. 

Over time, a diverse and well-nourished gut microbiome has been linked to reduced inflammation, stronger immune defenses, better nutrient absorption, and improved mood and mental health.

3. They May Help Regulate Blood Sugar 

The complex carbohydrates and fiber in Japanese sweet potatoes digest more slowly, leading to steadier blood sugar levels.

“Don’t let the word ‘sweet’ mislead you,” White said. “While sweet potatoes are high in carbohydrates, research suggests they may help regulate blood sugar levels.”

However, portion size matters, particularly for people with diabetes who are tightly managing blood sugar levels, as well as people following a low-carb or keto diet, said Davis.

For most people, pairing them with protein and healthy fats—like grilled fish and olive oil–sautéed greens—can help further stabilize post-meal blood sugar.

4. They Could Support Heart Health

Japanese sweet potatoes are also good for your heart because they’re rich in fiber and anti-inflammatory antioxidants while containing no saturated fat, according to Davis.

She noted that some varieties, like Murasaki Bako Sweet Potatoes, are even American Heart Association-certified as a Heart-Check Food, meaning they meet the organization’s nutrition requirements for foods that support cardiovascular health.

Their fiber content can help manage cholesterol levels by binding to cholesterol in your digestive system and carrying it out of the body. The lack of saturated fat and antioxidants also supports healthy blood vessels and reduces inflammation, lowering the risk of heart disease over time.

How Do They Compare to Other Sweet Potatoes?

Davis said that nutritionally, Japanese sweet potatoes are very similar to the orange-fleshed sweet potatoes most people are familiar with.

Their appearance and taste set them apart: They have purple skin with white flesh and are known for being slightly nuttier, sweeter, and drier than the orange varieties. 

Baking or steaming them helps preserve their nutrients, while roasting brings out their natural sweetness. Try them:

• As a side dish: Slice and roast with olive oil, garlic, and herbs.
• In salads: Cube and toss with leafy greens, nuts, and a vinaigrette.
• Mashed or pureed: Use in soups or as a creamy side.
• For breakfast: Bake and top with nut butter, cinnamon, and a drizzle of honey.