Once you take the work away most people have no idea what to do.
In 2003, Dr Harry Prosen stepped down as head of psychiatry at the Medical College of Wisconsin, but the then 71-year-old had no plans to retire. Rather, the doctor intended to focus on other “jobs” that would keep him busy.
Now 83, Prosen still sees several patients, consults for a number of organisations, recently reviewed a 600-page manuscript for a friend and regularly pores over a handful of medical journals because he “just wants to keep up,” he said.
It’s not just a love of working that has kept Prosen toiling away 30 hours a week as an octogenarian. He also sees keeping busy as a matter of life or death.
Prosen said he is certain that if he stopped working entirely, he would literally die not long after.
He could be on to something. A number of studies show that retirement is, in fact, bad for your health.
A May 2013 report published by the London-based Institute of Economic Affairs found that retirement increased the chances of suffering from depression by 40%, while it increased the probability of having at least one diagnosed physical ailment by about 60%. That impact was assessed after controlling for the usual age-related conditions.
Gabriel Sahlgren, director of research at the Centre for Market Reform of Education and author of the IEA report, was surprised by just how much retirement undermined health. He looked at 9,000 people across 11 European Union countries and found that across borders, people suffered in the same ways and to similar degrees.
In the first year of retirement, health actually improved — “It’s nice to get some rest from work,” he said — but two to three years later retirees’ mental and physical conditions began deteriorating.
Other studies have shown similar results. Between 1992 and 2005, Dhaval Dave, an associate professor of economics at Bentley University in Waltham, Massachusetts, looked at 12,000 Americans and found that, on average, people experience some sort of ailment within six years of retiring. Hypertension, heart disease, stroke and arthritis are common physical ailments, Dave said. He, too, found that depression increased after retirement.
Though retirement ages may differ from country to country — in China men retire at 60, in India people retire between 60 and 65 and in Norway it’s closer to 67 —studies done in other nations have produced comparable findings. Health problems, both physical and mental, are exacerbated by retirement, whether a retiree is 65 or 75.
There are a number of reasons why health declines after retirement, said Dave, but, mental and social stimulation are a large factor. For many people, work is where they are the most social and do the most physical activity. When that core social network is removed, health declines.
“If those social interactions disappear, you’ll get lonely,” said Sahlgren. “Research suggests that loneliness leads to mental illness and that could lead to physical illness because you stop taking care of yourself.”
A reduction in income can also affect health, said Sahlgren. People who make less money may buy cheaper foods, avoid going to the doctor as often as they should and abandon their gym membership, he said.
Mary Peterson doesn’t need a study to tell her how retirement affects health. The Muskoka, Ontario, 60-something lives in a community of mostly retirees and sees firsthand the effects of not working.
A surgeon friend had a stroke two months after retiring, while another friend started forgetting details after months of all-day TV watching, Peterson said.
“Once you take the work away most people have no idea what to do,” she said. “And that’s what leads to deterioration.”
Peterson’s husband retired from a stressful finance job when he was 55. Four years later he was diagnosed with cancer. While retirement wasn’t likely a factor in his illness, the possibility did cross her mind. “Health is a funny thing,” she said.
Her husband beat the disease and is now a healthy 66-year-old. But, Peterson said, he didn’t stay home after his work life ended — something she believes has contributed to his continued great mental and physical health. He decided to pursue his lifelong love of singing, joined a vocal group and practices nearly every day. Peterson believes his singing has helped keep him alive and well.
Beating retirement decline
When Prosen, the psychiatrist, looks around at his friends and acquaintances, the healthiest still work, volunteer or live an active and social life, he said.
That, say researchers, is the key to staying healthy mentally and physically well into retirement. Retirees must fill the social and physical activity gap the end of work leaves, transitioning into activities that keep them stimulated, Dave said. It can help to move to a community with other retirees, where social interaction can continue unabated or where there are organised activities, lectures and get-togethers.
There is, of course, another option: continue working.
Sahlgren points out that people are living longer than ever before. Many countries have life expectancies of close to or over 80 today, about a decade longer than in 1960. So there’s less reason to retire at 65.
Sahlgren does not suggest working until, say, you die at your desk, but rather believes that older people should not quit work cold turkey. Cutting down on the number of working hours is a better alternative than full retirement for many people, Sahlgren said.
“It may be beneficial to reconsider the kind of work and retirement balance that we’ve established,” he said. “That might be able to circumvent some of the negative health effects associated with not working.”
While Prosen said that he may one day stop seeing patients, he plans to continue working in some capacity until an illness forces him out of a job.
“Alzheimer’s could push me to retire,” he laughed, “but if I have a say that will never happen.”
To comment on this story or anything else you have seen on BBC Capital, head over to our Facebook page or message us on Twitter.