Purple sweet potatoes have become increasingly popular in recent years for their vibrant color and potential health benefits. But are they actually healthier than regular orange sweet potatoes? Here is a comprehensive look at the nutritional profile and health effects of purple sweet potatoes.
Nutritional Profile
Purple sweet potatoes owe their bright color to anthocyanins, antioxidant pigments that give foods like blueberries and red cabbage their hue. Anthocyanins have been linked to many health benefits. Here is how purple sweet potatoes compare nutritionally to regular orange sweet potatoes per 100 grams:
| Nutrient | Purple Sweet Potato | Orange Sweet Potato |
|---|---|---|
| Calories | 90 | 86 |
| Carbohydrates | 20.7 g | 20.1 g |
| Fiber | 3 g | 3 g |
| Sugar | 4.2 g | 6.5 g |
| Fat | 0.1 g | 0.05 g |
| Protein | 1.6 g | 1.6 g |
| Vitamin A | 14187 IU | 709 IU |
| Vitamin C | 2.4 mg | 2.4 mg |
| Manganese | 0.258 mg | 0.258 mg |
| Potassium | 337 mg | 337 mg |
As you can see, purple and orange sweet potatoes are very similar nutritionally. However, purple varieties contain way more antioxidant anthocyanins. Orange sweet potatoes contain more beta carotene, the antioxidant that gives them their vibrant color.
Anthocyanins
Anthocyanins are flavonoid antioxidants that give purple sweet potatoes their vivid purple hue. They have anti-inflammatory, antioxidant, and anti-cancer effects in the body.
Some of the main anthocyanins found in purple sweet potatoes include:
– Peonidin: This has strong antioxidant activity and may protect cells from free radical damage. It also has anti-inflammatory effects.
– Cyanidin: The most common anthocyanin found in foods, cyanidin is a powerful antioxidant that may reduce oxidative stress and inflammation.
– Malvidin: Studies show malvidin has potent antioxidant capacities and may help lower risk of chronic diseases.
Overall, the anthocyanins in purple sweet potatoes can help combat inflammation, protect your body from harmful free radicals, and potentially reduce the risk of chronic illnesses like heart disease and cancer.
Polyphenol Antioxidants
In addition to anthocyanins, purple sweet potatoes also contain a variety of other polyphenol antioxidants:
– Chlorogenic acid: This polyphenol is thought to promote lower blood sugar levels, improve cholesterol, and lower blood pressure.
– Caffeic acid: This antioxidant is linked to anti-inflammatory and antimicrobial activities that may boost your immune system.
– Ferulic acid: Ferulic acid is an antioxidant shown to neutralize free radicals, which may prevent chronic diseases and support healthy aging.
Vitamin A
One of the biggest differences between purple and orange sweet potatoes is their vitamin A content.
Orange sweet potatoes are very high in beta carotene, which your body converts into vitamin A. Just one medium baked orange sweet potato (114 grams) meets over 400% of your daily vitamin A needs (1).
Purple sweet potatoes contain some beta carotene, but significantly less than orange varieties. However, they do provide between 14-19% of your daily vitamin A needs per 100 grams (2).
Vitamin A promotes good vision, reproductive health, immune function, and organ health. It supports the mucus membranes that line your eyes, respiratory tract, gut, urinary tract, and other areas.
While orange sweet potatoes supply much more vitamin A, purple varieties still provide a decent amount plus their unique set of antioxidants.
May Promote Blood Sugar Control
Multiple studies have found that antioxidant-rich purple sweet potatoes may improve blood sugar regulation.
In one 8-week study, consuming purple sweet potato extract helped lower hemoglobin A1C levels (a marker of long-term blood sugar control) in people with type 2 diabetes. It also increased antioxidant status compared to a control group (3).
Another study gave people instant oatmeal containing either white or purple sweet potatoes. The purple sweet potato oatmeal resulted in significantly lower blood sugar levels after a meal compared to the white potato oatmeal (4).
The anthocyanins found in purple sweet potatoes may be responsible for their beneficial effects on blood sugar. Anthocyanins have been shown to boost insulin sensitivity and stabilize blood sugar levels after meals (5).
May Enhance Brain Function
The anthocyanins and chlorogenic acid found in purple sweet potatoes may promote brain health in several ways.
In animal studies, purple sweet potato extract enhanced learning and memory in mice with Alzheimer’s disease (6, 7).
Test-tube studies indicate that chlorogenic acid and anthocyanins found in purple sweet potatoes may reduce oxidative stress-induced damage in brain cells (8, 9).
The potent antioxidants in purple sweet potatoes may protect brain cells from free radical damage to enhance brain health. More human research is needed in this area.
May Support Immunity
Preliminary research indicates the nutrients in purple sweet potatoes may strengthen your immune defenses.
In one study, purple sweet potato extract enhanced immune cell activity and cytokine production in mice, which could strengthen immunity (10).
Cell studies reveal that chlorogenic acid reduces oxidative stress and inhibits the production of pro-inflammatory messaging molecules in immune cells (11).
Additionally, the antioxidant content of purple sweet potatoes may protect your immune cells against free radical damage to support their normal function. More studies are needed.
Easy to Incorporate Into Your Diet
Here are some easy ways to eat more purple sweet potatoes:
– Bake, roast, or steam them just like regular sweet potatoes. Add cinnamon, nutmeg, coconut oil, butter, or chocolate chips for extra flavor.
– Make sweet potato pancakes by shredding purple sweet potatoes and mixing with eggs, baking powder, cinnamon, and vanilla.
– Mash steamed purple sweet potatoes and combine with bananas, peanut butter, and milk for a tasty pudding.
– Blend cooked purple sweet potatoes into smoothies along with fruits, veggies, Greek yogurt, milk or nut milk.
– Make sweet potato toast by slicing sweet potatoes into thin slices, lightly brushing with oil, and toasting until crispy.
– Dice sweet potatoes and add to soups, stews or chili for extra fiber and nutrients.
Possible Downsides
Purple sweet potatoes are generally considered safe with very few side effects reported. However, some things to keep in mind are:
– Oxalate content: Purple sweet potatoes contain oxalates, compounds that may contribute to kidney stones in those prone to them. People with a history of oxalate-containing kidney stones should minimize high-oxalate foods.
– Allergies: Sweet potatoes belong to the nightshade family of vegetables, along with tomatoes, eggplant, and peppers. People with nightshade allergies may need to avoid or limit purple sweet potato intake.
As with any food, enjoy purple sweet potatoes in moderation as part of a healthy, balanced diet tailored to your individual health needs.
The Bottom Line
Purple sweet potatoes are nutritious root vegetables high in unique antioxidants called anthocyanins, which give them their vibrant color.
Due to their antioxidant content, purple sweet potatoes may help lower your risk of chronic illnesses, promote blood sugar control, and support immunity and brain function.
While not quite as rich in vitamin A as orange sweet potatoes, purple varieties still provide an array of nutrients and health benefits.
Purple sweet potatoes make a tasty, eye-catching alternative to regular oranges ones. Try baking, mashing, or blending them into your favorite dishes to take advantage of their nutritional value.
