Sweet Potatoes: One of nature’s truly great gifts!
Sweet potatoes are one of the oldest foods in the human diet. Their starch content is similar in every way to other root vegetables and tubers that have played prominent roles in human development. These starches have provided humans with a critical source of carbohydrates that has allowed for expansion of our brain size as a species and has been supportive of human health and the health of hundreds of human generations. Sweet potatoes are a great source of numerous nutrients that range from trace minerals to vitamin E, and from fermentable fiber to an array of carotenoids. In all, one cup of sweet potato contains more than 20% of the DRI for at least 10 nutrients. They can be a staple of a healthy diet and are the true definition of a "superfood" if such a thing exists!
Although both sweet and an incredibly rich source of carbohydrates, the glycemic index of sweet potatoes is moderate (46 if boiled or steamed and 82 if baked) to low depending upon the cooking method and temperature. While steaming or lower heat cooking techniques generate significantly lower glycemic indexes, eating sweet potatoes raw is not better. In fact, research suggests that some heat is best. Just several minutes of steaming, for instance, inactivates peroxidase enzymes in sweet potatoes that would otherwise degrade the variety of pigments present and can render them less beneficial to our health.
The greatest benefits derived from sweet potatoes may be found in some of the unique phytonutrients that they contain. One of those phytonutrients is sporamin, a unique storage protein that helps sweet potatoes heal when injured or damaged in the ground. This molecule, in synergy with other phytonutrients, has significant antioxidant value, anti-inflammatory properties.
While all sweet potatoes are extremely concentrated in carotenoids, purple sweet potatoes are exceptionally high in their anthocyanin content. In fact, antioxidant research has shown that the purple pigments peonidin and cyanidin provide purple sweet potatoes with an ORAC value that is 3.2x higher than blueberries on a per weight basis!
Famous Blue Zone and healthy populations that eat sweet potatoes as a regular part of their diet include the Okinawans and the New Guinea Highlanders. These and other populations have great levels of health from so many excellent lifestyle characteristics and sweet potatoes are just one more of these.
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