Genetics play a key role in living to 100

According to Thomas Perls, a professor of Medicine at Boston University and leader of the New England Centenarian Study, which has followed centenarians and their family members since 1995, around 25% of your ability to live to 90 is determined by genetics. But by age 100, that number jumps to 50%, and by age 106, it's 75%.

"Some people have this idea: 'If I do everything right, diet and exercise, I can live to be 150.' And that's really not correct," said Robert Young, who directs a team of researchers at the Gerontology Research Group.

Perls estimates that around 20% of the U.S. population has the genetic makeup to live to 100, assuming they also make consistent healthy choices.

Research has also found that not only do centenarians live longer, they tend to avoid or delay age-related diseases like cancer, dementia, and cardiovascular disease better than the general population.

The New England Centenarian Study found that 15% of its participants are "escapers," or those with no demonstrable disease by the age of 100. Meanwhile, around 43% are "delayers," or those who didn't develop an age-related disease until age 80 or later.

Some genes have been identified by researchers as being associated with longevity, including the presence of the apolipoprotein E gene called e2, which is believed to protect against Alzheimer's disease. Researchers note that every trait is a small piece in a larger puzzle that factors in socioeconomic status, race and ethnicity, and climate.

According to Perls, living beyond 100 requires a mix of different genetic variants that all have a relatively modest effect. Some of these variants are very beneficial and offer protective qualities like repairing DNA damage.

Other factors at play

Good habits also play a role, research has found. According to Claudia Kawas, who's been tracking the habits of those over the age of 90 in Southern California since 2003 as part of a University of California, Irvine study, there are links between longevity and even small amounts of exercise, social activities, and modest caffeine and alcohol intakes.

"Super-agers," or those who live beyond 80 with cognitive abilities on par with those 20 to 30 years younger, have reported having more warm, trusting, high-quality relationships with other people, research from Northwestern University has found.

"Keeping in good relationships could be one key to healthspan," said Amanda Cook Maher, a neuropsychologist at the University of Michigan and lead author of the study.

Research from Harvard University has found a link between optimism and longer lifespans among women in various racial and ethnic groups. Among participants in the study, the 25% who were the most optimistic also had the greatest likelihood of living beyond the age of 90 compared to the 25% who were the least optimistic.

If you're wondering how long you might live, Perls recommends looking at your family histories, as their lifespans are the strongest predictors of longevity.

If multiple family members have lived to a very old age, "you've potentially won a much greater chance of having purchased the right lottery ticket," Perls said. (Janin, Wall Street Journal, 10/11)

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