“She had cells that seemed younger than her age,” Esteller said.
The microbes that lived in and on her body, or her microbiome, are associated with low levels of inflammation, he added. Her microbiome had an abundance of a type of beneficial bacteria, Bifidobacterium, whose growth can be spurred by bacteria in yogurt. Branyas ate three yogurts a day.
“High levels of inflammation are related to advanced aging,” Esteller said.
Longevity genetics ‘notoriously confusing’
Immaculata De Vivo, a molecular geneticist at Harvard University who was not involved in the study, said the researchers’ explanations for Branyas’ longevity were “scientifically reasonable”.
But, she cautioned, “it’s always important to be careful when interpreting results from individual cases, as opposed to large, well-controlled population studies”. While genetics and metabolic factors might tilt the odds for or against disease, “disease causation is generally a matter of probabilities rather than absolutes”, De Vivo said.
In other words, good genes and microbiomes won’t keep you alive on their own.
Dr Mary Armanios, an oncologist and geneticist at Johns Hopkins School of Medicine, was less convinced. She questioned claims that certain genetic variants can predict longevity.
“The genetics of longevity are notoriously confusing,” she said. When researchers searched for variants linked to a long life, they compared the genes of younger people with those of people who were centenarians. But, she said, researchers don’t know if those younger people will live to be 100.
“What you want is a genetic profile that will predict,” she said. And that is hard to come by.
Armanios cautioned that genetics and a good microbiome are not even close to the whole story of why some people live so long. She noted that there are enormous differences in life expectancy linked to education and income levels. In Baltimore, she said, that adds up to a 20-year difference between people in the inner city and those in the suburbs.
“I do think there are obviously bad genetics that limit lifespan,” she said. “But I am not sure good genetics are sufficient to overcome socioeconomic limitations.”
A life well-lived
Branyas, for whatever reason, seemed exceptionally resilient.
She was born in San Francisco in 1907. Her parents were from Spain but had come to the United States for work. When Branyas was 8, her father died, and she and her mother moved back to Spain.
She married and had a son – who died at age 52 – and two daughters, who are now 92 and 94.
Members of her extended family died from common causes – Alzheimer’s disease, an accident, cancer, tuberculosis, kidney failure, heart disease. Branyas lived on and on.
She seemed to have had all the hypothesised prerequisites for a long life. If the genetic variants have the proposed effects, she was primed to avoid chronic disease. And her lifestyle seemed ideal.
She had a close circle of family and friends, Esteller said, adding that as her friends died, she made new ones. She and her family lived in the same town.
She lived independently until 2001, when difficulty walking led her to enter a nursing home. She played the piano until about five years ago.
“She lived a healthy life,” Esteller said.
This article originally appeared in The New York Times.
Written by: Gina Kolata
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