When Maria Branyas Morera died in August 2024 at the age of 117, she left behind more than just a legacy as the world’s oldest person. A new study of her genes, microbiome, and lifestyle reveals that Branyas’s cells functioned as if they were 17 years younger than her chronological age. Her gut microbiome, strikingly, resembled that of an infant.

These factors — combined with a lifetime of healthy habits — may explain how Branyas and other supercentenarians managed to live so long and so well.

Funny enough, Branyas, who was born in San Francisco in 1907 and spent most of her life in Catalonia, Spain, attributed her longevity to “luck and good genetics.” We can’t say for sure about luck, but she got the genes part right.

Good Genes But Also a Good Lifestyle

According to geneticist Manel Esteller of the University of Barcelona who led the new study, Branyas’ longevity was owed first and foremost to her “privileged genome.” Her DNA contained variations associated with a stronger immune system, protection against heart disease, and a reduced risk of cancer. But perhaps even more remarkable was her biological age, calculated by zooming in on DNA methylation — an epigenetic mechanism that modifies DNA without altering its underlying sequence. By this measure, Branyas’s cells were 17 years younger than her actual age.

“Remarkably, all the distinct algorithms of age based on DNA methylation yielded the same result,” the researchers noted.

The researchers also uncovered mutations in genes linked to immune function, heart health, and brain protection. For example, she carried a variant in DSCAML1, a gene associated with maintaining cognitive function, and another in MAP4K3, which has been linked to lifespan regulation in other species.

Even without this genetic advantage, living to 100 is exceptional. In the US, out of a population of 337 million people, there were 101,000 centenerians in 2024. Centenarians currently make up just 0.03% of the overall U.S. population, and they are expected to reach 0.1% in 2054. In the 1950s, there were only 2,300 Americans aged 100 and older. 

The vast majority of centenarians are 100 years old. Past a century of age, the numbers and prevalence decline dramatically. In Japan, a country home to the world’s largest population of people aged 100 and older, only 6.1% of centenarians are between 105 and 109 years old (semi-supercentenarians) and only 0.2% are over 110 years old (supercentenarians).

Remarkably, Branyas experienced only minor ailments in her later years, such as joint pain and hearing loss, and maintained her mental clarity until the very end. And her lifestyle choices likely amplified these genetic advantages.

The Gut Bacteria of an Infant

Branyas avoided alcohol and smoking, enjoyed daily walks, and adhered to a Mediterranean diet rich in fruits, vegetables, and — notably — three yogurts a day. This diet, researchers believe, may have helped cultivate a gut microbiome that was unusually youthful.

Apparently, the late supercentenarian’s gut closely resembled that of an infant.

“Microorganisms are critical in determining not only the metabolite composition of our body, but also inflammation, intestinal permeability, cognition, and bone and muscle health,” the researchers wrote.

While the exact mechanisms linking the microbiome to longevity are still unclear, Branyas’s case suggests that maintaining a healthy gut could be a cornerstone of aging well. For instance, her microbiome was rich in Bifidobacterium, a type of bacteria known for its anti-inflammatory properties.

Branyas’ immune system and metabolism were also unusual for her age. Using single-cell RNA sequencing, the researchers mapped out the different types of immune cells in her blood. They found an unusual abundance of age-associated B cells, a type of immune cell that typically accumulates in older individuals and is linked to autoimmune disorders. No surprise there considering her age. Yet, the woman showed no signs of such conditions.

Her immune profile also revealed a dominance of cytotoxic T cells, which are responsible for killing infected or cancerous cells. This aligns with previous studies showing that supercentenarians often have an expanded population of these cells. 

Daily Living for Longevity

And researchers saw once again where her healthy diet likely helped. Analysis of her blood revealed an exceptionally efficient lipid metabolism. She had very low levels of VLDL cholesterol and triglycerides, both of which are linked to cardiovascular disease. At the same time, her levels of HDL cholesterol, the “good” cholesterol, were remarkably high. This efficient lipid profile is associated with a reduced risk of dementia and other age-related diseases.

Additionally, she reportedly surrounded herself with family and friends, avoided stress, and stayed active both mentally and physically. These habits, supported by scientific evidence, are known to stave off dementia and other age-related declines.

“The picture that emerges from our study shows that extremely advanced age and poor health are not intrinsically linked,” the researchers wrote.

While Branyas’ combination of traits is rare, the study opens the door to intriguing possibilities. Could interventions targeting the immune system, metabolism, or gut microbiome help others achieve similar longevity? And could epigenetic therapies slow down the aging process itself?

These avenues are bound to be explored, especially as the world’s population of centenarians is on the rise. For now, Branyas’ legacy serves as an inspiration. She lived through two World Wars, the Spanish Civil War, the 1918 flu pandemic, and even COVID-19, which she contracted in 2020 but survived with no symptoms. “I think longevity is also being lucky,” she once said.

The findings appeared in the pre-print server BioRxiv.