How Old Is Your Body? Biological Age Differs Widely From Chronological Age

A landmark study has shown how biological age can be differs from chronological age and that some individuals age faster than the real age.

A team of researchers from New Zealand, Britain US and Israel who analyzed data from the Dunedin study in New Zealand, found that 38 year-old people could biologically be as old as 60 years. On the other end of the spectrum, they could also age slower than one year per year and stay young.

"We set out to measure aging in these relatively young people. Most studies of aging look at seniors, but if we want to be able to prevent age-related disease, we're going to have to start studying aging in young people," said first author Dan Belsky, an assistant professor of geriatrics in Duke University's Center for Aging.

The Dunedin study has been following since birth, individuals born in a specific town of New Zealand during 1972-73. Researchers used 18 parameters including lung function, kidney tests, cholesterol and even length of telomeres, the protective caps at the end of chromosomes which shorten with age, among other parameters to define an individual's biological age.

The researchers then obtained archival data for the study group when they were 26 and 32 years to determine the rate of ageing. They found that individuals found to be 'biologically' older at 38 years had also aged faster during their chronologically younger years, over the 12-year study period. This overturned the popular notion that ageing was a process that caught up when people chronologically aged.

The research also found that those biologically older than the other 38-year olds in the study group performed poorly in tests administered on people older than 60.

Additionally, college students who were asked to estimate the age of the study group from photos pointed out the biologically older participants to be older than their real self. This indicated that people old on the inside, also appeared older than their real ages.

Researchers said that only 20 percent of the ageing process can be attributed to genes and the rest was environment-perpetuated. Medicine can thus help intervention which can help people add healthy productive years to their lifespan.