People who look young really are ageing slower
Some lucky people look young for their age, while others appear old before their time; now, researchers from Dunedin can start to tell us why.
A method to measure the pace of ageing of people in their 20s or 30s has emerged from the University of Otago's long-running Dunedin Multidisciplinary Study, which has tracked more than 1000 people born in Dunedin in 1972-73 from birth to the present.
A large number of health measures, such as blood pressure, white blood cell count, liver and kidney function, have been taken regularly along with interviews and other assessments.
The paper, written by a team from the United States, United Kingdom, Israel, and New Zealand, was published today in the Proceedings of the National Academy of Sciences.
It revealed a panel of 18 biomarkers that could be combined to determine whether people were ageing faster or slower than their peers.
When these 18 measures were assessed together in 954 study members at age 38, researchers were able to set "biological ages" for each person. In contract to chronological ages, these ranged from 30 to nearly 60 years.
The same measures were then analysed from when the subjects were aged 26 and 32, to determine their "hidden pace of ageing", Dunedin study director Professor Richie Poulton said.
"As we expected, those who were biologically older at age 38 also appeared to have been aging at a faster pace. A biological age of 40, for example, meant that person was aging at a rate of 1.2 years per year over the 12 years the study examined," he said.
Most were found to be clustered around one biological year per chronological year, but others were found to be ageing as fast as three biological years per actual year, while some where staying "younger than their age", Poulton said.
Three subjects even had a pace of ageing less than zero - meaning they appeared to grow physiologically younger during their 30s.
Individuals who were ageing more rapidly were less physically able, showed brain ageing, suffered worse health, and looked older.
Beyond clinical indications, a person's experience of ageing was found to be influenced by their own perceptions of their well-being and by that of others.
With the world's population aged 80 years and over expected to approach 400 million by 2050, extending healthy lifespans could help relieve an "enormous global burden of disease and disability", he said.
The ultimate goal was to be able to intervene in the ageing process itself, before killers such as heart disease or cancer can strike, first author Dan Belsky, an assistant research professor at Duke University's Centre for Ageing, said.
"Ageing itself has to be the target to prevent multiple diseases simultaneously, otherwise it's a game of whack-a-mole."
Written by Katie Kenny. First appeared on Stuff.co.nz.
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