Written by Helen Chu, MS RDN, US Registered Dietitian
Approaching fall season, some of us are waiting to enjoy the flavour of roasted sweet potato and sweet potato dessert. Sweet potato, a starchy vegetable, is packed with vitamins C, antioxidants and fiber. Vitamin C plays a vital role in supporting our immune system. Sweet potato is also a good source of potassium which helps to regulate blood pressure.
Apart from the fact that sweet potatoes are highly nutritious, they also offer a number of health benefits.
Promotion of gut health and regular bowel movement
Sweet potato contains both soluble and insoluble fiber. Both types cannot be digested by our body. Fiber stays in the digestive system and promotes growth of good bacteria and contributes to a healthy gut.
Some soluble fibers absorb water and soften the stools whereas some insoluble fibers add bulk. Thus, fibers help promote regular bowel movement. One medium sized sweet potato provides 3 gm fiber. It has been established that a daily intake of 20-30 gm fiber helps to reduce risk of colon cancer.
Test-tube studies have indicated that orange and purple sweet potatoes contain anti-cancer properties. Sweet potato with orange flesh is rich source of beta carotene which is converted to vitamin A in our body. Beta carotene is an antioxidant which supports immune function and fights off damage to cells caused by unstable molecules called free radicals.
Anthocyanin, an antioxidant found in purple sweet potato, has been found to slow growth of certain types of cancer cells - in the stomach, colon, bladder.
Both orange and purple sweet potatoes are rich in antioxidants that help protect and prevent body from free radical damages but studies in humans is still needed.
Sweet potato is an excellent source of vitamin A. Vitamin A is key nutrient which helps to prevent dry eyes, night blindness. Both beta carotene and anthocyanin improve eye health by protecting eye cells from damage.
Caution for people with Diabetes:
Sweet potato has a medium to high glycemic index. If people with diabetes love the sweet flavor of sweet potato, do boil sweet potato to reduce glycemic index instead of having it fried, baked or roasted. Eat sweet potato with a good source of protein can help lower the glycemic load. However, individuals with diabetes should still watch the portion size of sweet potato.
Boil sweet potato to retain more beta carotene
Add a little fat, such as vegetable oil or olive oil, in cooking or eating can boost the absorption of beta carotene
Cook sweet potato with skin to minimize loss of vitamin C
Ways to add sweet potato to your diet:
Substitute white potato with sweet potato in stews, e.g. curry chicken stew
Bake or grill sweet potato
Add cooked diced sweet potato in soup, salad and congee
Prepare sweet potato fries instead potato fries
Mash sweet potato with milk for extra protein and calcium