Purple potatoes contain high concentrations of a variety of antioxidants, including phenolic acids, anthocyanins, and carotenoids, according to researchers from the University of Scranton in Pennsylvania. Due to their unique combination of antioxidants, purple potatoes can lower high blood pressure and risk for heart disease and stroke.
Moreover, sweet potatoes are also good source of complex carbohydrates. Complex carbohydrates are those carbohydrates that are made of three or more sugar molecules linked together. These carbohydrates are found vegetables, nuts, fruits, seeds and grains.
Complex carbohydrates take longer for your body to break down than simple ones, which helps to maintain a steady blood sugar level.
Sources:
http://www.everydayhealth.com/heart-health-pictures/foods-you-didnt-know-were-good-for-your-heart.aspx?xid=fb_EH_sf#/slide-3
http://www.fitday.com/fitness-articles/nutrition/carbs/what-are-complex-carbohydrates.html#b
