The oldest group of people in the country is a community of Seventh Day Adventists residing in Loma Linda, California.

 

 They have an average life expectancy of 88 years (a full ten years longer than the U.S. average). One reason may be that Adventists don't drink or smoke, and many follow the vegetarian diet the church advises. But not all members do, and even the meat-eaters live significantly longer than average. Dr. Gary Fraser, a researcher with the Loma Linda University School of Public Health who is researching the community, told the BBC. "At this moment we don't really know, but people who go to church regularly- whatever faith they have- live longer, and there's no question about that."