Hollywood stars like Matt Damon, Madonna, Katie Couric and Alicia Keys are not only healthy, but they have actively promoted healthy lifestyles by starting their own charities.  From Damon’s Water.org, which is devoted to implementing clean water programs and promoting health and sanitation in Africa, to Couric’s National Colorectal Cancer Research Alliance, which promotes early medical screening and funding research to develop better tests, treatments and ultimately a cure for colon cancer, find out what 10 celebrity do-gooders stand for.