PHOENIX – Alex Alejandre lost 75 pounds in a year. His wife, Mary, lost 40.

They want to set a good example for their 17-year-old son, Nathan, and take a personal stand against obesity, which can lead to diabetes and other serious health problems, especially in Native Americans. 

"The health of my child is everything to me. I want him to grow up to be healthy," said Alex, a member of the Salt River Pima-Maricopa Indian Community. With the help of a community program, his family is getting healthy.

Native American adults are 50 percent more likely to be affected by obesity than non-Hisp...