Study of 117-year-old María Branyas Morera reveals youthful gut microbiome despite short telomeres

Scientists studying María Branyas Morera, the world's oldest verified living person who died at 117, found her body displayed both extreme old age and youthful features, including short telomeres but low inflammation and a young-like gut microbiome. The findings were published in Cell Reports Medicine in September 2025. Branyas, born in 1907, survived two world wars, the Spanish Civil War, and Covid-19 at age 113. Researchers collected blood, saliva, urine, and stool samples, revealing epigenetic clocks estimated her biological age as roughly two decades younger than her chronological age, despite signs of an ageing immune system and clonal haematopoiesis. Her genome contained rare protective variants, and her Mediterranean-style diet, regular yoghurt consumption, and close family ties may have contributed. The single-person study cannot establish universal longevity formulas, but suggests ageing and illness are distinct, offering insights into delaying disease despite biological wear.