Blood Sugar Benefits
Many people think about starchy root vegetables as a food group that could not possibly be helpful for controlling their blood sugar. That’s because many people realize that food starches can be converted by our digestive tract into simple sugars. If foods are especially concentrated in starch, there can often be a risk of too much simple sugar release in our digestive tract and too much pressure upon our bloodstream to uptake more sugar. (The result in this situation would be an overly quick elevation of our blood sugar level.) What’s fascinating about sweet potatoes is their ability to actually improve blood sugar regulation—even in persons with type 2 diabetes. While sweet potatoes do contain a valuable amount of dietary fiber (just over 3 grams per medium sweet potato) and if boiled or steamed can carry a very reasonable glycemic index (GI) rating of approximately 50, it may not be either of these factors that explains their unusual blood sugar regulating benefits.
Recent research has shown that extracts from sweet potatoes can significantly increase blood levels of adiponectin in persons with type 2 diabetes. Adiponectin is a protein hormone produced by our fat cells, and it serves as an important modifier of insulin metabolism. Persons with poorly-regulated insulin metabolism and insulin insensitivity tend to have lower levels of adiponectin, and persons with healthier insulin metabolism tend to have higher levels. While more research on much larger groups of individuals to further evaluate and confirm these blood sugar regulating benefits, this area of health research is an especially exciting one for anyone who loves sweet potatoes.
Antioxidant Nutrients in Sweet Potato
Sweet potatoes contain a wealth of orange-hued carotenoid pigments. In countries throughout Africa, in India and in the Caribbean, sweet potatoes have been shown to be a highly effective way of providing school age children with sizable amounts of their daily vitamin A. In some studies, sweet potatoes have been shown to be a better source of bioavailable beta-carotene than green leafy vegetables. Because sweet potatoes are available in many countries on a virtual year-round basis, their ability to provide us with a key antioxidant like beta-carotene makes them a standout antioxidant food.
- Low JW, Arimond M, Osman N et al. A food-based approach introducing orange-fleshed sweet potatoes increased vitamin A intake and serum retinol concentrations in young children in rural Mozambique. J Nutr. 2007 May;137(5):1320-7. 2007.
- Zhang ZF, Fan SH, Zheng YL et al. Purple sweet potato color attenuates oxidative stress and inflammatory response induced by d-galactose in mouse liver. Food Chem Toxicol. 2009 Feb;47(2):496-501. Epub 2008 Dec 13. 2009.
- Bahado-Singh PS, Wheatley AO et al. Food processing methods influence the glycaemic indices of some commonly eaten West Indian carbohydrate-rich foods. Br J Nutr. 2006 Sep;96(3):476-81. 2006.
- Information in this article from http://www.whfoods.org