Working keeps us young, a new study shows, while a long period of unemployment does the same damage to our DNA that aging causes.

The study at Imperial College London and the University of Oulu, Finland, studied DNA from 5,620 men and women born in Finland in 1966.

DNA is arranged in our cells in long strings called chromosomes. Each chromosome has a protective tip at each end called a telomere, like the plastic tabs at each end of a shoelace.

As we age, the telomeres gradually become shorter. Eventually they can’t protect the chromosomes, which then suffer physical damage from wear and tear, like a shoelace with no plastic tip.

The Finnish men who were unemployed for more than two years lost their telomeres faster than men with jobs, as if they were aging faster.

At the University of Ottawa, geneticist Earl Brown explains why that’s a bad thing. “The point is that when you copy your DNA, you lose a little bit on the end each time, just because of the way the process goes. So they get shorter and shorter.

“If you start to get these ends too short, then you get unstable chromosomes,” he said.

That’s why cells can’t divide and divide forever. In the lab they can divide a few dozen times, “and then they get old and die.”

That happens to people as well when the telomeres get too short, usually through normal aging.

“Then you go the way that all people go. We all die,” Brown said.

In fancier terms, “it’s associated with the loss of cell viability” — meaning the cells don’t do their jobs any more. “You’re not working with a full deck of genes at that point.”

As well, there are genetic conditions where telomeres “get too short too quickly, and those people have premature aging” and early death.

“We all want our telomeres to stay long and be a basis for good biology ... (to) keep everything working.”
(An exception to the general rule is the special case of sperm and egg cells. They keep long telomeres forever, so that the next generation will have a full set to start its life.)

So far, the Imperial College study found the aging phenomenon only in men, but the researchers suspect that’s because they didn’t have enough unemployed women to give them adequate data. They’re hoping for further research on women.

Dr. Jess Buxton told reporters that earlier studies have shown that stress also shortens telomeres and “we have now shown that longterm unemployment may cause premature aging too.”

In 1995 the Canadian Medical Association Journal published an overview of research relating unemployment to sickness and death.

“Unemployment and economic issues may seem beyond the usual bounds of health care,” it concluded. But researchers found “the evidence strongly supports an association between unemployment and a greater risk of morbidity (physical or mental illness or use of health care services), both at the population and individual levels, and a greater risk of mortality at the population level.”