She Lived to 117: Scientists Studied María Branyas Morera to Discover Why Her Body Aged So Slowly

When María Branyas Morera died in August 2024 at the age of 117 years and 168 days, she left behind far more than an extraordinary longevity record.

She left scientists with something much more valuable: biological clues.

Branyas, who was officially recognized as the world’s oldest living person before her death, had agreed to participate in scientific research during the final years of her life. Researchers collected biological samples and examined her genetics, blood proteins, metabolism, epigenetic patterns and gut microbiome in an attempt to understand what made her body so unusually resilient.

The results, published in Cell Reports Medicine in 2025, offered a fascinating picture of extreme human longevity.

Her chronological age was undeniable. She really had lived for more than 117 years.

But several biological measurements suggested that some aspects of her physiology looked considerably younger than expected.

Researchers reported a younger-looking epigenome, unusually low levels of inflammation, efficient lipid metabolism, a gut microbiome containing bacteria associated with healthier ageing, and genetic variants that may have provided protection against some age-related diseases.

One University of Leicester research team involved in the project reported that an epigenetic clock estimated her biological age to be, on average, about 23 years younger than her chronological age. That does not mean that a 117-year-old body literally became the equivalent of a 94-year-old body in every respect. Biological age is not a single number that perfectly describes every organ and tissue. Instead, the result suggests that certain molecular markers of ageing were unusually youthful for someone of her chronological age.

That distinction is important.

And it may be the most interesting part of her story.

Chronological Age Is Not the Whole Story

Most people think of ageing as something that can be measured simply by counting birthdays.

If someone is 50 years old, they are biologically 50.

If someone is 80, they are biologically 80.

But biology is more complicated.

Two people who are the same chronological age can have very different levels of physical function, disease risk and cellular ageing. One 70-year-old may remain active and independent, while another may already be dealing with multiple chronic conditions.

The World Health Organization describes ageing as the result of accumulating molecular and cellular damage over time, but emphasizes that these changes are not linear or identical among individuals. The relationship between chronological age and biological ageing is therefore much less straightforward than simply counting years.

This is where the concept of biological age becomes important.

Biological age attempts to describe how old the body's cells and physiological systems appear to be based on measurable biological characteristics.

Scientists can estimate aspects of biological ageing by examining things such as DNA methylation, inflammation, metabolic markers, immune function and other molecular changes.

One particularly interesting approach involves the epigenome.

The epigenome does not change the DNA sequence itself. Instead, it consists of chemical modifications and regulatory mechanisms that help determine which genes are active or inactive.

Over time, environmental exposures, lifestyle, disease, stress and normal ageing can influence these patterns.

Researchers have discovered that some DNA methylation patterns change in relatively predictable ways with age. These patterns can be used to create what scientists call epigenetic clocks.

The U.S. National Institute on Aging explains that these clocks can estimate biological age based on changes to DNA methylation and that some measures of epigenetic ageing have been associated with later-life health outcomes.

In María Branyas's case, the epigenetic findings were particularly intriguing.

Her chronological age was 117.

But some of her molecular ageing markers looked substantially younger.

What Scientists Actually Studied

The research surrounding Branyas was unusually comprehensive.

Rather than examining only one gene or one disease marker, scientists used a multiomics approach.

That means they looked at several biological layers at the same time.

Researchers analyzed her genome, transcriptome, metabolome, proteome, epigenome and microbiome, comparing the results with larger groups of people where possible.

At around age 116, biological samples including blood, saliva and stool were collected.

The blood provided information about proteins, metabolism, inflammation and cardiovascular-related biology.

The saliva and other biological material helped researchers investigate genetic and molecular characteristics.

The stool sample was particularly useful for studying the gut microbiome — the enormous community of microorganisms living inside the digestive tract.

This was important because modern ageing research increasingly recognizes that longevity is not controlled by a single “longevity gene.”

Instead, ageing appears to emerge from the interaction of genetics, metabolism, immune function, inflammation, environment, behavior and chance.

Branyas offered scientists a rare opportunity to see what happens when many of these factors come together in one exceptionally long-lived person.

Her Epigenome Looked Younger

Perhaps one of the most striking findings involved epigenetics.

Researchers created an epigenetic clock using DNA methylation patterns and found that Branyas's estimated biological age was substantially below her chronological age.

The University of Leicester team reported an average biological-age estimate around 23 years younger than her chronological age.

Again, this should not be interpreted as meaning that every part of her body was biologically 23 years younger.

Different tissues age differently.

An epigenetic clock also measures a particular molecular pattern rather than directly measuring the functional age of every organ.

Nevertheless, the finding is consistent with an important idea in modern ageing science: some people may accumulate certain molecular signs of ageing more slowly than others.

The National Institute on Aging describes biological age as reflecting accumulated damage, physiological changes and loss of function, while noting that epigenetic clocks are one method researchers use to estimate it.

This raises a fascinating question.

What allowed Branyas's epigenetic ageing to remain relatively slow despite her extraordinary chronological age?