Sometimes living to be 120 sounds like a great idea, other times not so much. Ask people if they’d like to live that long and the answer is generally something like: “It depends on the quality.”

Whatever your thoughts on becoming a centenarian, here are 10 things you should know about living to a ripe old age.

Has science found a longevity gene? “No,” says Robert Moyzis, professor emeritus of biological chemistry at UC Irvine, “but there are a variety of genes that have significant impact on how long each of us lives.”

More specifically, Moyzis and his colleagues have found – by studying those who have lived long lives – that there are parts of certain genes that indicate whether you are more, or less, likely to engage in risk-taking or addictive behaviors. And choosing behaviors – how much you exercise, smoke, eat, see a doctor – does indeed determine how long you live.

“One allele can only do so much,” says Moyzis. “I believe we have free will, and how we exercise that, matters.”

Longevity, by the way, is only a recent concern for humanity. It’s just within the past 100 years that the infant mortality rate in first-world countries has become low enough to talk about long life for the majority.

The constant evolution of the human species is evidenced in this. Humans, for example, have been able to live longer lives because DNA repair genes have evolved – in only the past few thousands years – to fix a lot of previously mortal flaws. So, too, have we evolved to fight off more pathogens that significantly shorten our days.

What do doctors mean when they say you have “longevity syndrome?” Medically, it’s defined as a longer-than-expected lifespan – usually 10 years longer than average – that is shared in families because they pass down a genetic mutation which keeps their good cholesterol at levels at or above 75 mg/dL.

In general, what does science say about genetic influences on how long we live? A famous 1995 study on almost 3,000 pairs of Danish twins (born between 1870 and 1900) has long been held to be the definitive word on this. It found that only about 25 percent of our life expectancy is dictated by our genetic material.

The other 75 percent? How we live our lives.

What’s more important to a long life – diet or attitude? Two rather big studies – one at Yale, one in Norway – pointed convincingly to positive attitude adding, on average, 7.5 years to an individual’s life, regardless of health problems, gender, even financial situation.

What’s a “blue zone”? In a nutshell, as defined by National Geographic’s Dan Buettner after years of research: Blue zones are regions on Earth with the longest life expectancy, disability-free life expectancy or concentration of people over 100.

What do people in these zones have in common? According to Buettner’s “The Blue Zones” (National Geographic, 2008), they:

• Make moderate physical activity a part of their lives.

• Eat beans, whole grains and garden vegetables.

• Make family a priority.

• Have a sense of purpose.

• Drink a little red wine.

• Slow down.

• Participate in their community throughout their life.

• Live with those who share their values.

Loma Linda, in San Bernardino County, is one of only eight elite blue zones in the world. Why? It’s home to a community of Seventh-Day Adventists who strictly adhere to the Sabbath as a day of focus on faith, family and rest. Further, the group believes that their bodies form a temple for the holy spirit. This encourages them to maintain a kind of physical purity that is manifested by a vegetarian diet with no alcohol, caffeine or soda intake. All of these behaviors have been shown to contribute to lengthened lifespans.

The average white Adventist male in Loma Linda lives 7.3 years longer than his white non-Adventist Californian counterpart. The average white Adventist female lives 4.4 years longer than her counterpart. If the Adventists we’re talking about are also vegetarian, make that 9.5 years for the men and 6.1 years for the women.

Harriett Jameson and Asa Eslocker, lecturers at the University of Virginia School of Architecture, have studied three of the blue zone cultures extensively. Seeking more information about how the landscapes of Okinawa, Sardinia and Loma Linda contribute to the longevity of their cultures, the duo report finding several remarkable commonalities:

• Dense, walkable towns where the elderly are integrated into the social structure of the communities.

• Spirituality embedded in everyday routine, such as walking to daily mass in Sardinia or hiking to a utaki prayer site in Okinawa.

• A sense that it’s safe to walk down the street.

• Sunny, warm climates that are good for gardening and mental and physical health.

• Significant landscape elements, such as mountains or the ocean, that help foster a sense of place and a connection to the daily environment.

Where can I move in the U.S. to live the longest? If you’re not heading to Loma Linda to live among the Seventh-Day Adventists, consider moving to Hawaii, where women live to be 87.22 and men 83.17. Or Florida or Arizona.

Wanna stay home? Please do. California ranks eighth among states for life expectancy, with an average of about 84 years, factoring in both sexes and all races, .

Where can I move elsewhere in the world to live the longest? Monaco, where the average life expectancy is 89.68 years, a decade longer than for the average American. Credit the great climate, clean environment, Mediterranean diet, abundant personal wealth and, dare we say it, state-funded health care.