Scientists studying Brazil’s oldest citizens say they may be closer to understanding why some people live far longer than average, with new research pointing to unique genetic and biological factors behind extreme longevity.

A new viewpoint published in the journal Genomic Psychiatry highlights findings from an ongoing Brazilian study focusing on centenarians and supercentenarians. While most people live around 70 years, a small number reach 100, and an even rarer group live beyond 110.

Researchers say Brazil offers a unique advantage because of its highly diverse population, shaped by Indigenous roots, European colonisation, African ancestry and immigration from many parts of the world.

The study includes more than 160 centenarians from across the country, including about 20 supercentenarians. Some participants remained mentally sharp and physically independent even after turning 100. In a few rare cases, long life appeared to run in families, including one family with four women aged between 100 and 110.

Scientists believe this diversity may help reveal genetic traits linked to long life that are not visible in studies of more uniform populations. Many of the participants also came from poorer regions with limited access to health care, suggesting that strong biological protection, rather than modern medicine alone, played a major role in their longevity.

Researchers also noted that some Brazilian supercentenarians survived Covid-19 before vaccines were available, pointing to particularly strong immune systems.

Experts say expanding longevity research to include diverse populations like Brazil’s is essential to better understand ageing and improve health outcomes worldwide.

With inputs from BBC