Of all the job conditions known to undermine the wellbeing of employees, few have been as well studied as long work hours and overtime. While we still need convincing evidence that reducing work hours may improve health, the body of knowledge about how work hours erode worker health should persuade employers that this is an area with considerably more potential for health improvement compared to conventional approaches like screenings and lifestyle interventions.
- A review of data from the Whitehall II study (which I described in my previous post about effort and reward balance) found that risk of heart disease, including fatal heart attacks, increased as the average number of overtime hours worked increased, to the point where those working four to five hours of overtime a day had a 1.56-fold increase in risk.
- A study of American workers found that, compared with people who worked 11 to 39 hours per week, the risk of having high blood pressure was 17% greater for people who work 41 to 50 hours per week and 29% greater for those who work more than 50 hours per week.
- A 2014 meta-analysis published in Lancet found that employees in low socio-economic groups who worked 55 hours or more per week had a risk of developing Type II diabetes 30% greater than comparable employees who worked 35 to 40 hours per week. This held true even when the data was adjusted for age, sex, BMI, and lifestyle factors, such as leisure-time physical activity, smoking, and alcohol consumption. It also remained true after shift workers were excluded from the analysis.
- A 2005 study of more than 100,000 work records determined that the risk of work-related injury goes up in lockstep with the number of hours worked per day or per week. And the researchers determined that the relationship between long hours and injury existed across a wide range of industries, job categories, and worker demographics.
- Long work hours have been linked to alcohol abuse. And European studies, including those summarized in a New York Times post, have shown that employees who regularly work more than 11 hours a day had more than double the risk of depression.
No one knows the exact mechanism through which long work hours grind away at employee health. The obvious possibility is that employees working excessive overtime have less time for physical activity, sleep, food preparation, social interaction, and other healthful activities. On the other hand, Japanese researchers, who identified a relationship between long working hours and heart attacks, proposed a biological pathway from long hours, to changes in the autonomic nervous system, to high blood pressure and, ultimately, to coronary heart disease.
Work-life conflict may also be a waypoint on the path from long hours to reduced wellbeing, according to authors of one landmark study. In the study of “work time, work interference with family, and psychological distress,” the researchers found that long hours at work increase work-family conflict, which, they concluded, leads to depression and other stress-related health problems. They offered advice to employers and to employees:
Employers need to realize that it behooves them to find better ways to organize and structure work. Employees need to be aware of the consequences of the choices they make about how they use their time.
Indeed, at least one analysis has shown that the well documented relationship between working hours and weight gain may be due to employees’ choices and inclinations, and not just employer workforce management. That is, employees who are disinclined to partake in physical activity, healthy food preparation, and a full-night’s sleep, may opt in to longer hours. The researchers concluded, “Policies aiming to reduce obesity prevalence targeting working hours may not be effective.” But they left open the possibility that environmental changes — such as healthy food choices and opportunities for physical activity at the workplace — may help mitigate the BMI increases that accompany long work hours.
The complexities of working long hours and its influence on employee wellbeing are broad. Future Health Shifting posts will explore in greater detail how overtime is related to fatigue, sleep disorders, job performance problems, shift work, job type, burnout, and time-off policies, and its role in a society where more employees are “on” 24/7, and increasing numbers work multiple jobs and as freelancers.
Long Work Hours Take Center Stage
Long work hours have been in the news lately. President Obama has raised the income threshold for overtime pay exemption. His primary stated objective is to assure that more people are getting paid for the time they spend working, though one may speculate that a potential outcome will be to reduce the amount of overtime Americans work. Jeb Bush was quoted, perhaps out of context, as saying Americans need to work more hours.
These positions evoke an important discussion about long work hours, in an America where only half of full-time employees report regularly working 40 hours a week or less. Arguments that more work hours equate to greater productivity have proven to be oversimplified.
- An analysis by The Economist pointed out that Greek workers toiled an average of 600 hours more than Germans in 2012, while Germans’ productivity was 70 percent higher.
- In her book The Overworked American, economist Juliet Schor chronicled how companies ranging from Kellogg’s to Medtronic have found productivity (and wellbeing) to increase with shortened workdays.
- Stanford economist John Pencavel recently reviewed historical research and industrial data and determined that output tends to decline above certain thresholds of work hours. And he points out that long work hours and fatigue have been linked to medical error, motor vehicle accidents, and airline flight crew error.
The U.S., as well as other nations around the globe, should recognize that labor policies, such as regulations related to work hours and overtime pay, are intertwined with public health and, consequently, health care expenditure. In the interim, employers should take health into consideration when making decisions that affect the work schedules and the workloads of their workforce.
Now on Medium.com: Read my post about the Japanese concept of karoshi (death by overwork) and karo jisatsu, suicide due to overwork. On my old blog, this post drew more readers than all my other posts (nearly 100!) combined. — Bob