An excellent source of vitamin C, vitamin K, manganese and a good source of fiber - with just 80 calories a cup - blueberries  ranked eighth in total polyphenol capacity per serving out of over 100 common foods, according to the USDA. Tufts University has found that blueberries may slow and even reverse age-related brain decline in animal studies. The same scientists believe blueberries could someday protect astronauts against the radiation-induced free-radical damage experienced during extended space flight. Blueberries for dessert might offset the increase of free radicals and drop in antioxidant levels after an overindulgent meal. Blueberry bonus: Like their little red cousin, the cranberry, blueberries contain compounds that may help ward off urinary tract infections. 

Information source (Dole Nutrition Institute):