This racial group includes any of the original peoples of North, South and Central America who maintain tribal affiliation or community attachment. The five leading causes of death among American Indians and Alaska Natives are heart disease, cancer, unintentional injuries, diabetes and chronic liver disease/cirrhosis, according to the U.S. Centers for Disease Control & Prevention's Office of Minority Health & Health Disparities. Native Americans suffer disproportionately high rates of obesity, infant mortality, mental health problems and substance abuse. In 2008, an estimated 4.8 million people were classified as American Indian or Alaska Native (alone or in combination with one or more other races), according to the U.S. Census Bureau. About one third of American Indians live on reservations or other trust lands. The federal Indian Health Service is charged with meeting the health needs of 562 federally recognized tribes residing on reservations. Indians who live elsewhere have limited or no access to these services; many have difficulty accessing health care because of lack of insurance. Other factors that contribute to poor health care include geographic isolation and poverty. Many Native Americans rely on traditional healing practices. Updated February 2010