Gut microbiome of world’s oldest woman may reveal secrets to longevity

The world’s oldest person Maria Branyas Morera died at 117 years old – and researchers believe that her gut microbiome may hold the secrets to longevity.

To uncover the key to a long life, researchers analysed different aspects of Morera’s health including her genes, transcriptome, metabolism, proteins, microbiome and epigenetics.

The team, based at the Josep Carreras Leukemia Research Institute in Spain, also conducted extensive interviews addressing her clinical history and lifestyle habits such as sleep, diet, exercise and social interactions.

They found that Morera had a number of healthy lifestyle habits that are known to contribute to longer lifespans such as physical exercise, a healthy diet and maintaining social ineractions throughout her life.

The researchers write: “In spite of several emotionally painful events during her last years of life, like her son’s death, she kept a strong physical and mental health throughout life with good sleep habits, balanced Mediterranean diet, and active social life.

“She largely enjoyed from quality time with family and friends, playing with dogs, reading books, growing a garden, walking, and playing the piano.

“She suffered from Covid-19 and chronic age-related diseases like bronchiectasis, oesophagus diverticulum, and osteoarthritis, with limited movement and high dependency during her last months of life.

“She never suffered from other prevalent age-related diseases like cancer or neurodegenerative diseases, unlike siblings.”

However, despite these healthy practices, the researchers believe the secret to Morera’s long life may lie in her gut.

The team used rDNA analysis to examine Morera’s microbiota, comparing the results with 445 samples from control individuals including 250 women and 195 men aged 61 to 91 years.

The team found that Morera had a higher microbiome diversity than the control female population, with higher levels of actinobacteriota – one of the four major gut microbiota which contribute to gut health and immunity – in comparison with the control populations from both genders.

According to the team, this increase in actinobacteriota was due to the elevated amount of bifidobacteriaceae, particularly bifidobacterium – a finding they say contrasts sharply with the typical decline of this bacterial genus in older individuals.

“Bifidobacterium is thought to be a beneficial bacterium contributing, among other processes, to anti-inflammatory responses, an observation that links with the low levels of inflammation markers in the metabolomics study,” the researchers wrote.

“High content of Bifidobacterium has also been associated with the production of short-chain fatty acids and conjugated linoleic acid, observations that relate to the “healthy” lipid-related biomarker profile detected by 1H-NMR.

“Importantly, the use of Bifidobacterium as a probiotic that could slow down the progression of many ageing-associated disorders is gaining momentum.”

The team highlight that 117-year-old Morera ate around three yogurts every day containing the bacterium streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus.

These bacterium are known to favour the growth of the the healthy bacteria in the gut, and the researchers say this could be an example of a dietary intervention that is associated with healthy ageing and long lifespan.

The researchers wrote: “Overall, these results suggest that the studied extreme supercentenarian possesses a microbiome that confers an increased likelihood for a healthy extended lifespan. This is also consistent with her adherence to a Mediterranean diet, which might have contributed to the described unique microbiome composition.”

The paper is yet to be peer reviewed.