Happy birthday, Emma Morano! The Italian woman certified as the world’s oldest living person by Guinness World Records turned 117 on Tuesday.
Morano famously eats eggs every day and, aside from an unhappy marriage early in life, has been single since 1938. "I didn't want to be dominated by anyone," she told The New York Times last year. Morano is likely the last person born in the 19th century who is still alive.
But what factors truly allow some people to live such long lives? Morano and other super-centenarians — people who are 110 and older — are providing important clues for experts who study extreme longevity.
“It’s incredible and very rare. If I could get there, I would,” Dr. Thomas Perls, professor of medicine and geriatrics at Boston University and Boston Medical Center, told TODAY.
“They have a lot to tell us about healthy aging.”
At any one time, there are only about 300 super-centenarians worldwide, said Perls, who heads the New England Centenarian Study. In the U.S., they occur at a rate of about one per five million people.
The oldest verified person who has ever lived was Jeanne Louise Calment of France, who died at 122.
Think you can get there? Here’s what you need to know about extreme aging:
1. Genes play a different role at different stages of life
When it comes to the average person’s aging, about 75 percent is determined by environment and behavior, while about 25 percent is genetic, Perls noted.
“We all on this planet have an average genetic makeup or blueprint that should get us to about our late 80s,” he said. “If you smoke, drink, weigh too much, don’t exercise, you’re going to die a lot sooner.”
If you do everything right — keep fit, eat a vegetarian diet, avoid cigarettes and alcohol, manage your stress — you’re more likely to reach your full longevity potential. Seventh-Day Adventists famously do all of those things, and they live to an average age of 86 for men, and 89 for women.
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But if you get to 110, the role of genes and environment become reversed. At that stage, about 70 percent of aging is controlled by genes, and just 30 percent by the environment, Perls said.
2. It’s about the right combination of genes
Super-centenarians like Morano aren't born with just one “aging well” gene, but many of them.
Out of the 30,000 genes or so in the human genome, super-centenarians have the right variations in at least 130, making them very rare.
“It’s like winning the lottery,” Perls said. “We call those genetic signatures of exceptional longevity.”
The genes regulate the many different biological mechanisms that contribute to aging. In the case of people like Morano, they slow it down and decrease the risk of diseases like heart disease, stroke, diabetes, cancer and dementia.
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3. Women are much more likely to enjoy extreme longevity
About 85 percent of centenarians are women. At the most extreme ages, 110 and older, that number grows to 90 percent.
“Men are the wimps when it comes to aging; women definitely win the longevity marathon,” Perls said.
The mechanisms for that are unclear. One factor is that men who get age-related diseases are much more likely to die from them than women.
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4. Super-centenarians can delay or escape major diseases
Women who get to the age of 110 or more aren’t just alive, they tend to be in “really spectacular shape,” Perls noted. It’s not surprising to see them live independently and be mentally sharp.
Researchers believe they live so long because they don’t develop the diseases that kill the rest of us until the last five years of their extremely long lives, a hypothesis known as compression of morbidity.
You have to compress the time that you're sick towards the end of your life; otherwise, how are you going to get to extreme old age?
5. Bottom line
It’s not possible for humans to routinely reach 117, but many of us should be able to live until our late 80s and early 90s in good health, Perls said. Super-centenarians like Morano can help us learn how to get there.