Japanese sweet potatoes, also known as satsumaimo, are a nutritious and delicious type of sweet potato popular in Japanese cuisine. With their vibrant purple flesh and sweet taste, satsumaimo offer various health benefits and can be a great addition to a healthy diet.
What are Japanese sweet potatoes?
Japanese sweet potatoes are a variety of sweet potato native to Japan. They have a unique purple-reddish skin and vibrant purple flesh. Their flavor is drier and richer than regular orange sweet potatoes, with a sweet chestnut-like taste.
Some key features of satsumaimo:
- Vibrant purple skin and flesh
- Sweet, dense and creamy texture
- Richer, drier flavor compared to regular sweet potatoes
- Higher sugar content due to starch conversion during growth
The purple color of satsumaimo comes from anthocyanin pigments. These pigments act as antioxidants in the body and offer various health benefits.
Are they nutritious?
Yes, Japanese sweet potatoes are highly nutritious.
Some of the key nutrients found in satsumaimo (based on a 100g serving) include:
- Calories – 119
- Carbs – 27.1g
- Fiber – 3g
- Vitamin A – 15187 IU (304% DV)
- Vitamin C – 30mg (50% DV)
- Potassium – 348mg (8% DV)
- Antioxidants like anthocyanins
As you can see, satsumaimo are low in calories and high in fiber, making them quite filling. They provide very high amounts of vitamin A in the form of beta-carotene. They also contain decent amounts of vitamin C, potassium and powerful antioxidant pigments.
Are they low in carbs and good for dieting?
Compared to starchy potatoes, satsumaimo are lower in carbohydrates. A 100g serving provides 27g of carbs, mostly in the form of starch and fiber.
This carb content is lower than the same serving size of white potatoes (36g carbs), sweet potatoes (23g carbs) and Russet potatoes (33g carbs).
The fiber content (3g per 100g) is also higher than regular potatoes. This helps slow down digestion, leading to a steady release of glucose instead of spikes in blood sugar.
Overall, the lower carb and higher fiber content makes Japanese sweet potatoes a better option for diets like low-carb, keto, paleo and diabetic diets. The nutrients and fiber keep you feeling fuller for longer on fewer carbs.
Benefits of Japanese Sweet Potatoes
Here are some of the main health benefits offered by Japanese sweet potatoes:
1. Excellent Source of Antioxidants
The vibrant purple color of satsumaimo comes from antioxidants called anthocyanins. These pigments possess strong antioxidant properties and can help scavenge harmful free radicals in the body.
Diets rich in antioxidants have been tied to benefits like:
- Reduced inflammation
- Lower risk of heart disease, diabetes and cancer
- Slowing aging and promoting longevity
- Vision protection
- Boosting brain function
The anthocyanins in satsumaimo also give them an extremely high vitamin A content in the form of beta-carotene. Just 100g provides over 300% of the RDI for vitamin A.
2. May Help Manage Blood Sugar
The fiber and nutrients in Japanese sweet potatoes can help regulate blood sugar levels.
Fiber slows down digestion, leading to a more gradual rise in blood sugar after meals instead of rapid spikes. The anthocyanins also appear to boost insulin sensitivity and glycemic control.
In one study, diabetic rats fed purple sweet potatoes showed better blood sugar regulation compared to a control group. More research is needed to confirm these effects in humans.
3. Support Gut Health
Satsumaimo provide prebiotic fiber that feeds the good bacteria in your gut microbiome.
The anthocyanins also get metabolized into compounds that may help reduce inflammation, offer antioxidant effects and provide other benefits in the GI tract.
A healthy gut microbiome is linked to benefits like better immunity, improved digestion, enhanced mood and lower disease risk.
4. May Promote Heart Health
Some research indicates that anthocyanin antioxidants can support heart health by:
- Lowering blood pressure
- Reducing LDL cholesterol oxidation and plaque buildup
- Improving blood flow and artery function
- Providing anti-inflammatory effects
More human research is needed to confirm these potential heart protective effects. But the combination of antioxidants, fiber, potassium and other nutrients in satsumaimo appears heart healthy.
5. Contains Cancer-Fighting Compounds
The anthocyanins in satsumaimo act as antioxidants and anti-inflammatories, which may help fight cancer.
Test tube studies show they can slow the growth and spread of certain cancer cells and induce cancer cell death. The exact mechanisms are still being researched.
While more human studies are needed, the current data is promising for the cancer-fighting potential of satsumaimo.
Using Japanese Sweet Potatoes for Weight Loss
Here are some tips on incorporating satsumaimo into a diet for weight loss:
1. Swap Them for Starchy Carbs
Japanese sweet potatoes make an excellent lower-carb substitute for regular potatoes, rice, bread, pasta and other starchy carbs.
Using them in place of some of your usual high-carb foods reduces overall carb intake, while still providing fiber, nutrients and satisfaction.
2. Try Them Mashed, Baked or Roasted
Satsumaimo have a creamy sweet texture when cooked, making them perfect for mashing. They can be baked whole or cut into wedges and roasted with a little olive oil.
Baking or roasting enhances their natural sweetness and gives them a crispy exterior while keeping the interior soft and moist.
3. Add Them to Salads
Raw satsumaimo can be enjoyed grated or cut into chunks as part of a salad. Their sweet flavor and vibrant color liven up any salad.
Toss them with leafy greens, vegetables, nuts, lean protein and a vinaigrette or creamy dressing. The fiber and nutrients will help fill you up.
4. Make Sweet Potato Toast
Slice Japanese sweet potatoes into thick slices and toast them for a delicious low-carb “toast”. Top with avocado, nut butter, ricotta cheese or an egg for a hearty breakfast or snack under 300 calories.
5. Use Them in Soup
Cube and roast sweet potato pieces, then add them to vegetarian soups and stews for extra fiber and nutrients. They’ll soak up the flavors of the broth.
You can also puree roasted satsumaimo with some broth for a creamy sweet potato soup to help curb cravings.
Potential Concerns
Japanese sweet potatoes are considered very healthy and safe for most people. But here are a few things to keep in mind:
Oxalate Content
Satsumaimo contain oxalate compounds which can contribute to kidney stone development in those prone to them. If you’ve had kidney stones, limit intake of satsumaimo and consult your doctor.
Glycemic Index
While the glycemic index (GI) of satsumaimo is lower than regular potatoes, it is still considered high at 70-90.
This means the carbs are digested and absorbed quickly. People with diabetes need to be mindful of portions and incorporate satsumaimo into an overall low-GI diet.
Allergies
Sweet potatoes are among the more common food allergies, especially in infants and children. If you suspect an allergy, avoid satsumaimo.
Pesticide Residues
Buying organic satsumaimo can help minimize exposure to pesticide residues found in conventional varieties. Or properly peel and wash non-organic potatoes.
Overall, satsumaimo are considered very safe when enjoyed reasonably as part of a healthy diet.
The Bottom Line
Japanese sweet potatoes offer an array of nutrients, fiber and antioxidants like anthocyanins.
Compared to regular potatoes, they are lower in carbs and higher in nutrients like vitamin A. The fiber and antioxidants provide benefits for blood sugar, gut health, immunity, heart health, vision and more.
Enjoying satsumaimo in moderation as part of an overall healthy diet can provide great health benefits. Their sweet flavor and versatility also makes them easy to incorporate into a diet for sustainable weight loss or maintenance.
While not a magic bullet for weight loss on their own, Japanese sweet potatoes are a nutritious substitute for starchy carbs and an excellent addition to any diet.