How old are you? How old do you look?
The answers to those two things are linked, more than you might think. A new Danish study of twins published this week suggests that looking younger is connected to living longer, and what doctors call your “perceived age” is more important than your chronological age in many ways.
The study, published in the British medical journal BMJ, followed Danish researchers who tested more than 1,800 pairs of twins over age 70 for physical and cognitive attributes. They also took photos of the twins' faces. Then nurses, trainee teachers and peers who didn’t know the twins were asked to guess their ages.
The researchers then kept track of how long the twins survived over the next 7 years.
From the Associated Press:
The experts found that people who looked younger than their actual age were far more likely to survive, even after they adjusted for other factors like gender and environment. The bigger the difference in perceived age within any twin pair, the more likely it was that the older-looking twin died first.
They also found a possible biological explanation: people who looked younger also tended to have longer telomeres, a key DNA component that is linked to aging. People with shorter telomeres are thought to age faster. In the Danish study, the more fresh-faced people had longer telomeres.
From U.S. News & World Report:
Common genetic factors that influence both survival and perceived age may help explain the findings, the study authors explained.
"Perceived age -- which is widely used by clinicians as a general indication of a patient's health -- is a robust biomarker of aging that predicts survival among those aged 70 and older and correlates with important functional and molecular aging phenotypes," Kaare Christensen and colleagues wrote in their report.
From the BBC:
Professor Tim Spector, a UK expert who has been doing his own twin research, said: "We are also finding this in our study.
"It's probably a combination of genes plus environment over a lifetime that are important."