Economic researchers in Japan (where there is a culture of long hours and karoshi – death by overwork) analysed the employment habits and cognitive test results of 3,000 men and 3,500 women above the age of 40 in Australia, including retired and unemployed people.
They found that a part-time job is the best balance between keeping the brain stimulated and becoming completely exhausted through stress.
People who worked about 25 hours a week tended to get the best scores. Those who didn’t work at all scored about 20% lower on the series of tests (reading, numbers and patterns).
Working 40 hours a week was linked to a slightly smaller cognitive deficit but working 55 hours or more was worse than being retired or unemployed.
Working over 50-55 hours is known to cause heart problems in men in particular and an increase in error rates and accidents. The Whitehall study of 10,000 civil servants also found that people who worked working 55 hours a week did worse on cognitive tests than those who kept to 40 hours. Despite this body of knowledge the UK government still opted out of the European Working Time Directive.
Many countries have extended or scrapped the state retirement age and many people face the prospect of working into their 70s. Finnish experts have already warned that people may not be physically or mentally capable of sustaining the effort required to continue in their jobs.
Some companies , like BMW, have invested in modifying the workplace to cater for older employees but they are probably an exception.
Marianna Virtanen, a Finnish Occupational Health expert (they are hot on OH in Finland) who led the Whitehall studies in the mid-80s said that the new research seemed to show tat “Middle-aged and older people should limit their working hours to keep their cognitive capacity fit“.
She did wonder whether a long working week caused a drop in cognitive ability or whether a drop in cognitive ability led to people working longer hours to compensate. She conceded however that “In certain jobs where there is a lot of intense focus and concentration is needed, working long hours may be more exhausting to cognition“.
More recently there was inter-departmental infighting between the Department of Health and the DTI about opting out of the EU Working Time regulations (which set a maximum of 48 hours). Health had commissioned research which clearly showed that working over 50 hours a week, especially for men, led to and increased risk of heart disease and stroke.
The latest news from University College, London, based on a study of over 500,000 workers from the US, Europe, and Australia, is that working more than 55 hours a week increases the risk of a heart attack by 13%.
Compared to people working a standard 40 hour week stroke risk increased by 10% if you worked up to 48 hours a week and by 27% if you worked up to 54 hours a week.
Working 55 hours or longer increased the stroke risk by a massive 33%.
Working long hours means you have less time to exercise or look after yourself, you probably eat fast food for the convenience and may drink more to help you relax.
Of course there are some extreme workers who appear to thrive on working long hours but how long can they keep it up?
Researchers from Northwestern University studied around 300 rural African-American teenagers. Those from low-income families who exhibited high levels of self-control, and were thus more likely to achieve their goals, had immune cells that were biologically much oder than their actual age.
Rapid ageing of these cells has been linked to premature death and its thought to be due to long-term high levels of stress hormone.
“To achieve upward mobility these youths must overcome multiple obstacles and often do so with limited support from their schools, peers, and families. Even if they succeed, these youths may go on to experience alienation in university and work-place settings and discrimination if they are African-American”
“Collectively these experiences seem likely to cause persistent activation of stress response systems”
Professor Greg Miller went on to say “For low-income youths, self-control may act as a double-edged sword facilitating academic success and psychological adjustment while at the same time undermining physical health”
In the research those with high self-control were able to focus better on long-term rather than short-term goals. were less depressed, used substances less frequently, and were less aggressive – regardless of their gender, family income or education
In addition those from low-income families were more likely to have the ageing immune cells.
Previous studies have shown that poorer children with better self-control were also at greater risk of heart disease because of their obesity, high blood pressure and levels of stress hormones in their blood.
The researchers add “These patterns suggest that for low-income youth resilience is a skin deep phenomenon wherein outward indicators of success can mask emerging problems with health”
They also think that providers of “character-building programmes” should include health education to help the youth mitigate health problems that stop them achieving their full potential. Low-income youths who do well in school and stay out of trouble are thought to have overcome disadvantage but it’s only half the full story it seems.
It would be interesting to know if these findings translate into other cultures and countries or whether they are only applicable to African-Americans from poor backgrounds.
It’s not just women who are putting their health at risk (see “Stress can be a killer for women ..“).
Unfit men who work long hours are doubling their risk of dying from heart disease. And it doesn’t matter whether or not the work is physically demanding. Work itself increases your heart rate and blood pressure.
According to Denmark’s National Research Centre for the Working Environment if you work longer than 45 hours and don’t take exercise you run twice the risk of dying than fit men who also work long hours but exercise.
Their study, published in the journal Heart, looked at 5,000 men aged 40 to 59 and tracked their working hours and fitness levels over 30 years. One in five of the men worked longer than 45 hours a week and if they were unfit these were the ones who were at most risk. Even working between 40 and 45 hours increased the risk by almost 60% compared with men who worked less than 40 hours.
Physically fit men were least at risk no matter how many hours they worked – not just of dying from heart disease but from other causes as well. High levels of fitness counter the negative effects on the body and speed up recovery time allowing you to sleep better and leaving you less tired and irritable.
The Daily Mail reported that full-timer workers in the UK work 1.5 hours a week longer than the EU average of 39.9 hours. Of course our government opted out of the Working Time Directive despite earlier warnings of the ill effects of working over 50 hours (See “Taking work to extremes“).
Apparently only workers in Romania and Bulgaria work longer hours and the UK has one of the highest heart attack rates in the world – someone having a heart attack every two minutes.