Research on centenarians has become more common with clinical and general population studies now having been conducted in France, Hungary, Japan, Italy, Finland, Denmark, the United States, and China.
[6] A preliminary study carried out in Poland showed that, in comparison with young healthy female adults, centenarians living in Upper Silesia had significantly higher red blood cell glutathione reductase and catalase activities and higher, although insignificantly, serum levels of vitamin E.[7] Researchers in Denmark have also found that centenarians exhibit a high activity of glutathione reductase in red blood cells.
[13] Other research carried out by the New England Centenarian Study has identified 150 genetic variations that appeared to be associated with longevity which could be used to predict with 77 percent accuracy whether someone would live to be at least 100.
For example, many people in the New England Centenarian Study experienced a century free of cancer or heart disease despite smoking as many as 60 cigarettes a day for 50 years.
[16] Similarly, centenarian research carried out at the Albert Einstein College of Medicine found that the individuals studied had less than sterling health habits.
[20] A 2011 study found people with exceptional longevity (aged 95 and older) not to be distinct from the general population in terms of lifestyle factors such as regular physical activity, diet or alcohol consumption.
[21] A study indicates gut microbiomes with large amounts of microbes capable of generating unique secondary bile acids are a key element of centenarians' longevity.
[29] In 2024, Saul Justin Newman published a pre-print paper finding that supercentenarians and extreme age records tend to come from areas with no birth certificates, rampant clerical errors, pension fraud, and short life spans.