(CNN) Spanish for "beautiful hill," Loma Linda, California is nestled between mountain peaks in the middle of the San Bernardino Valley. The city is known as an epicenter of health and wellness, with more than 900 physicians on the campus of Loma Linda University and Medical Center.

But that's not Loma Linda's only wellness claim to fame. This city of 21,000 is one of the five original blue zones , regions in the world where people live longest and are the healthiest. In fact, the people in this community tend to live eight to 10 years longer than the average American.

Experts say that's because Loma Linda has one of the highest concentrations of Seventh-day Adventists in the world. The religion mandates a healthy lifestyle and a life of service to the church and community, which contributes to their longevity.

'I never had stress'

"As far as I am concerned, stress is a manufactured thing," Dr. Ellsworth Wareham told CNN's Chief Medical Correspondent Dr. Sanjay Gupta in 2015 as part of a Vital Signs special on blue zones.

Wareham was 100 years old at the time and still mowed his front yard.

The five original Blue Zones.

"I never had stress," said Wareham, a life-long Seventh-day Adventist. "I have a philosophy: You do the best you can. And the things you can't do anything about, don't give any thought to them."

A heart surgeon by trade, Wareham assisted in surgeries until he was 95 years old, and told Gupta that he would still be able to operate at the age of 100.

"I could do open heart surgery right now. My hands are steady, my eyes are good," Wareham said. "My blood pressure is 117. I have noticed no deterioration in my mental ability with my age. If you gave me something to memorize, I would memorize it now just as quickly as when I was 20."

The role of vegetarianism

Wareham passed away last year , at the age of 104. Like 10% of the Adventist community, Wareham was a vegan. Another 30% are lacto-ovo vegetarians who eat dairy and eggs, while another 8% eat fish but not other meat. Vegetarianism is so prevalent that no meat can be purchased at the cafeterias at the university and medical center.

"Even our non-vegetarians are relatively low meat consumers," said Dr. Michael Orlich, the principal investigator of the Adventist Health Study-2, dedicated to examining the link between healthy lifestyle factors and disease in 96,000 Seventh-day Adventists in the United States and Canada.

"The average for non-vegetarians is only about two ounces of total meat a day, which is quite low," Orlich said.

consume less than 46 pounds a year. Low is an understatement. Based on US Department of Agriculture statistics on meat sold, Americans were expected to consume 222 pounds of red meat and poultry per person last year. In comparison, the Seventh-day Adventist meat eaters in the studyconsume less than 46 pounds a year.

What does that vegetarian lifestyle accomplish? A lower weight, for one. Vegans in the study had an average body mass index (BMI) of 23, well below the healthy cutoff of 25, Orlich said. Meat eaters in the study -- no matter how little they ate -- had an average BMI of 29, just shy of being considered obese.

Healthy lifestyle factors

Other key factors to longevity: Only 1% of the Seventh-day Adventist community in the study smokes. Little to no alcohol is consumed. Daily exercise out in the fresh air of nature is the norm. The church advocates a life of service, so dedication to volunteering, humanitarian and mission work is typical, which contributes to a sense of community.

Dr. Ellsworth Wareham mowing his lawn at age 100 (photo 2015)

Religion is key to their lives. Adventists have a "weekly date with God," in which they are to attend church, do no work, and dedicate the day to rest and rejuvenation.

"If your life is God directed, don't interfere with him, he is a pretty big person," Wareham told Gupta with a chuckle. "It gets you free of stress."

A subset of research on the community, called the Biopsychosocial religion and health study, looked at 20,000 Adventists and found that it was their connection the church that jumpstarted both their healthy habits and their emotional wellness.

"Those that were religiously engaged had a healthier diet, did more exercise and had more emotional wellness and less depression," said study co-author Kelly Morton, a professor of medicine and psychology at Loma Linda University. "And they did live longer."

Morton is deep into a new study analyzing the resilience characteristics of the oldest members of the community, those over age 100. Again, they are finding that religious engagement is an important factor in their longevity.

"It seems being highly connected to this church relationship, to this religious engagement activity, gives you the community of wellness to carry you into your later years," Morton said.

Add all of these factors together and what do you get? A healthier body, less likely to succumb to diseases tied to obesity, such as diabetes, high blood pressure, cancer and heart disease. Research on Seventh-day Adventists, which began in the 1950s, has consistently shown that connection.

Exercise in the fresh air is a key part of the Seventh-day Adventist lifestyle.

"In our Adventist Health Study-2 vegetarians tended to have lower blood pressures, lower LDL cholesterol, less prevalence of the metabolic syndrome, and less diabetes," Orlich said. "Broadly defined vegetarians, which includes the pesco- and the semi-vegetarian, have a lower risk of colorectal cancer by about 22%. Vegans have a lower risk for prostate cancer."

Dr. Ellsworth Wareham mowing his lawn at age 100 (photo 2015)

The first Adventist Health Study , which began in the '90s, was a detailed analysis of longevity and the factors in the religion's lifestyle that contributed to it. The study linked the increase in a longer life span to five simple habits: no smoking, keeping to an ideal weight of below 25 BMI, eating a plant-based diet, eating nuts regularly and regular physical activity.

"If you had all those factors in the right direction, so to speak, they predicted about a 10-year differential in mortality within the Seventh-day Adventist population," Orlich said."

Is it too late?

Few of us practice these healthy lifestyle habits, much less do them all at once. The good news, says Orlich, is that it's never too late to start.

"The bulk of evidence suggests that changing a few simple lifestyle factors can have a profound difference in the risk of major diseases and the likelihood of living a long life," Orlich said. "The body has an amazing ability to, um, you know, heal itself to some degree.

Take smoking for example. Many Baby Boomers are reformed smokers, addicted at a time when smoking was the norm in society.

"If you've stopped smoking for more than say, 20 or 30 years, you're hard to distinguish from somebody who has never smoked," said Orlich.

And if you're a couch potato, the good news is that starting any sort of exercise is going to be beneficial for you.

"The biggest bang for your buck is definitely going from little or no intentional physical activity to just a modest amount, like a bit of moderate walking a couple times a week," Orlich said. "So it's rarely too late to start adopting a healthy lifestyle. People can usually get impressive benefits even in a short length of time."