Work weeks that averaged 60 hours or more over three decades appear to triple the risk of diabetes, cancer, heart trouble and arthritis for women, researchers said. The risk begins to climb when women put in more than 40 hours and takes a decidedly bad turn above 50 hours, they said.
"Women - especially women who have to juggle multiple roles - feel the effects of intensive work experiences and that can set the table for a variety of illnesses and disability," said Allard Dembe from Ohio State University in the US.
"People do not think that much about how their early work experiences affect them down the road. Women in their 20s, 30s and 40s are setting themselves up for problems later in life, said Dembe. Researchers analysed data from interviews with almost 7,500 people and found that men with tough work schedules appeared to fare much better.
"Women tend to take on the lion's share of family responsibility and may face more pressure and stress than men when they work long hours, previous research shows. On top of that, work for women may be less satisfying because of the need to balance work demands with family obligations," said Dembe.
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According to him, companies benefit in terms of quality of work and medical costs when their workers are healthier. More scheduling flexibility and on-the-job health coaching, screening and support could go a long way toward reducing the chances employees become sick or die as a result of chronic conditions, he said.
Researchers averaged the self-reported hours worked each week over 32 years and compared the hours worked to the incidence of eight chronic diseases - heart disease, cancer (except skin cancer), arthritis or rheumatism, diabetes or high blood sugar, chronic lung disease including bronchitis or emphysema, asthma, depression and high blood pressure.
They also examined the results by gender. A minority of the full-time workers in the study put in 40 hours or fewer per week. Fifty-six per cent worked an average of 41 to 50 hours; 13 per cent worked an average of 51-60 hours; and 3 per cent averaged more than 60 hours. The results among female workers were striking.
The analysis found a clear and strong relationship between long hours and heart disease, cancer, arthritis and diabetes, said Dembe. Men who worked moderately long hours (41 to 50 hours weekly) had lower risk of heart disease, lung disease and depression than those who worked 40 hours or fewer, but higher incidence of arthritis, researchers said.
The findings were published in the Journal of Occupational and Environmental Medicine.