We generally assume that working too much is bad for our health. But what exactly is unhealthy about this is unclear. Is it working long hours that increases our risk of developing health issues? Or is it something else, like Michael’s compulsive work mentality, that is harmful for health? A study unravels the difference between behavior (working long hours) and mentality (a compulsion to work, or what we call workaholism). A survey and health screening of 763 employees found that work hours was not related to health issues, while workaholism was. Whether or not they worked long hours, people who obsessed over work reported more health complaints and had increased risk for metabolic syndrome; they also reported a higher need for recovery, more sleep problems, more cynicism, more emotional exhaustion, and more depressive feelings than employees who merely worked long hours but did not have workaholic tendencies. Unlike people who merely work long hours, workaholics struggled to psychologically detach from work. However, workaholics who loved their jobs were somewhat protected from the most severe health risks.

Hayon Thapaliya for HBR

Hanna, a finance director at an international home care retailer, works long hours. She’s usually in the office from 9am to 5pm, but at home, when her three children go to sleep, she’ll work another four hours, not closing her laptop until midnight. She sometimes also works on weekends. But even though she works 60 to 65 hours per week, she told us that she can “switch off” when she needs to, and that she still feels energetic every day. She hasn’t had to worry about her health.

Michael, the director of strategy for an American insurance company, does not work as much as Hanna. His workdays usually start at 8am and finish no later than 6pm, and he often leaves work at 3pm on Fridays. But even though he works an average of 45 hours a week, and is single with no kids, he has a hard time “switching off” and unwinding from his job — he is constantly checking his email and worrying about work. A few months ago, at a routine health check, his doctor noted he had high LDL cholesterol, which raises his risk for cardiovascular disease and diabetes. He was prescribed medication to lower it.

We generally assume that working too much is bad for our health. But what exactly is unhealthy about this is unclear. Is it working long hours that increases our risk of developing health issues? Or is it something else, like Michael’s compulsive work mentality, that is harmful for health?

What our research shows

We sought to unravel the difference between behavior (working long hours) and mentality (a compulsion to work, or what we call workaholism). We conducted a study in 2010 at the Dutch subsidiary of an international financial consulting firm with over 3,500 employees. We asked employees to complete a survey and then sign up for a health screening conducted by medical staff. 763 employees completed both.

What Is Workaholism? The term “workaholic” was coined in 1971 by the psychologist Wayne E. Oates, who referred to “an uncontrollable need to work incessantly” as an addiction. Workaholics are characterized by having an inner compulsive drive to work hard, thinking about work constantly, and feeling guilty and restless when they are not working. Workaholism often goes hand in hand with working long hours, but the two are distinct: it’s possible to work long hours without being obsessed with work, and it is possible to be obsessed with work but only work 35 hours a week or less.

The survey asked about participants’ workaholic tendencies (e.g., “I feel guilty when I am not working on something,” and “I put myself under pressure with self-imposed deadlines when I work”), their work skills, work motivation, and their work hours in an average week. It also asked if they experienced various psychosomatic health issues such as headaches and stomach problems. The health screenings gave us information about their various biomarkers (such as waist measurement, triglycerides, blood pressure, and cholesterol), which, when aggregated, are a reliable gauge for an employee’s risk of developing cardiovascular diseases and diabetes — what is referred to as Risk for Metabolic Syndrome (RMS). We also controlled for a host of factors such as gender, age, education, and family history of cardiovascular disease.

We found that work hours were not related to any health issues, while workaholism was. Specifically, employees who worked long hours (typically more than 40 hours a week), but who did not obsess about work, did not have increased levels of RMS and reported fewer health complaints than employees who demonstrated workaholism. We found that workaholics, whether or not they worked long hours, reported more health complaints and had increased risk for metabolic syndrome; they also reported a higher need for recovery, more sleep problems, more cynicism, more emotional exhaustion, and more depressive feelings than employees who merely worked long hours but did not have workaholic tendencies.

The experiences of Hanna and Michael, individuals whom we interviewed separately, outside of this study, align with these results. Hanna works long hours, but she is not mentally pre-occupied with work. When she finishes work for the night, she feels fulfilled and falls asleep easily. In the morning, she feels refreshed for a new workday. She told us, “I take my work very seriously while I’m working, but I forget about work the minute I decide I’ve done enough for the day.” Michael, on the other hand, has a compulsion to work hard and feels restless when he is not working. He continues to ruminate about his job and often finds it difficult to fall asleep and recharge before the next morning. When asked about his general stress levels, he mentioned that he “cannot remember the last time not feeling stressed or anxious about work.”

Unlike people who merely work long hours, workaholics struggle to psychologically detach from work. And we know that ongoing rumination often goes together with stress, anxiety, depression, and sleep problems, and it impedes recovery from work. Stress levels in workaholics are therefore often chronic, which leads to ongoing wear and tear on the body.

Here’s a quick explanation of why: To cope with stress, the body activates several systems (e.g., cardiovascular, neuroendocrine). So say you’re facing an important deadline. As you approach it, your stress hormones (e.g., cortisol), pro- and anti-inflammatory cytokines (e.g., interleukin-6), and blood pressure would likely go up. But after the deadline, these would return to their original levels, known as the “set points.” When you’re working an excessive workload and continually pushing your system beyond its range, you may re-set your set points. Elevated blood pressure may become chronic, and cortisol levels stay elevated. When your biological systems keep working around elevated set points, you have a greater risk of cardiovascular disease (CVD), diabetes, and even death.

Does it matter if you love the work?

Most workaholics are aware of their obsessive work habits, and friends and family will often warn them about the possible health risks. But a common defense is that they love their jobs. Linda, a personal injury lawyer whom we also interviewed separately from our study, readily admits to her work addiction but says she simply enjoys her work too much to change. Linda works for a medium-sized law firm in Canada and although her hours are exceptionally low for a lawyer (40 hours per week), she feels guilty when she is not working and often tries to come up with solutions for her clients off the job. As a result, she finds it difficult to fully engage in play with her five-year-old after work. She often experiences headaches and difficulty sleeping, as she ruminates about work and thinks up new ways of tackling work challenges. When talking to her husband and a trusted colleague about the ongoing headaches and sleep problems, they both urged her to visit the doctor — but she initially resisted. She told us, “There is really not much wrong with me, at least not physically. I just need more hours in the day.”

We wanted to see if enjoying the work mitigates the negative health effects of workaholism. Looking at the data from our study, we differentiated between workaholics who reported being highly engaged with their work — meaning they enjoyed their work, felt vigorous at work, and got easily absorbed in their work — and workaholics who reported low work engagement. We found that both types of workaholics reported more psychosomatic health complaints (e.g., headache, stomach problems) and mental health complaints (e.g., sleep problems, depressive feelings) than non-workaholics. However, non-engaged workaholics had higher RMS — a 4.2% higher risk — than engaged workaholics. (This number might seem small, but even a small increase can pose a serious health risk.)

This suggests that loving your work can mitigate some of the risk associated with obsessing over it. We also found that engaged workaholics reported having more resources at home and at work compared to non-engaged workaholics. Engaged workaholics reported receiving more social support (e.g., advice, information, appreciation), from their supervisor, co-workers, and their spouse, than their non-engaged counterparts. They also scored higher on communication skills, time management skills, and general work skills, and they reported much higher intrinsic motivation for work than non-engaged workaholics.

We think that this arsenal of resources may help engaged workaholics prevent initial health complaints from developing into more severe health risks. In Linda’s case, after listening to her husband’s concerns, she eventually consulted her doctor. The doctor did a general health check, and as Linda suspected, the results did not reveal any concerns in terms of physiological health. But her doctor referred her to a counselor to work on the sleep problems Linda mentioned during the check-up.

If we look at all of our examples, it’s clear that while Hanna, Michael, and Linda all work hard, the way they engage with work differs substantially, and hence, their health risk differs as well. Due to Hanna’s long work hours, her stress levels are high at times, but because they return to baseline levels, her stress is not chronic and she does not have the related mental or physical health risks. Michael has an obsessive work mentality, and he does not enjoy his work, which causes ongoing stress and frustration, frequent anxiety attacks and feelings of depression, and also elevated risk for cardiovascular disease. Linda has a similar compulsive work mentality, but she loves her job and reports having a supportive family. While she experiences some sleep issues and headaches, she does not have an elevated risk for cardiovascular diseases.

Two key messages — and their caveats

These stories and our research findings reveal two key messages: First, when it comes to effects on health, working long hours is not as bad as obsessing over work. But this warrants an important disclaimer: The employees in our sample worked a maximum of 65 hours per week, and therefore we do not know the health outcomes of working longer hours. It may be quite difficult to detach from work, engage in recovery activities, or get enough sleep if one works 70 hours per week or more. Still, it seems that more than hours, our thoughts and feelings about work impact our subjective well-being and health risks.

The second key message from our study is that workaholics who love their jobs are somewhat protected from the most severe health risks, and this may be because they feel that their work is worth all the hard work they put in. But this brings up another caveat: Although we found that engaged workaholics had lower physiological health risks (lower RMS) than non-engaged workaholics, they still reported more depressive feelings, sleep problems, various psycho-somatic health complaints, and a higher need for recovery than non-workaholics. These are all signs that well-being among workaholics, regardless of how much they love their job, can be impaired.

Avoiding the negative effects of workaholism

Our research suggests some potential solutions to help keep stress levels manageable and prevent health risks. The first step is to acknowledge when a relationship to work is unhealthy — when it feels out of control and is undermining outside relationships. The next step is to regain control over your work behavior. One way to do this is by setting clear rules for how many hours you will work each day. This can help you accept that there is a point at which you’ve done enough work for the day. If you have trouble “switching off,” you might want to stop working two or three hours before bed. Taking up enjoyable non-work activities, such as seeing friends, watching a movie, reading a book, or learning a new skill, can also help you psychologically detach from work.

It can also be useful to reflect on the reasons why you work excessively and compulsively. We found a striking difference in work motivation between engaged and non-engaged workaholics. Whereas engaged workaholics worked because they enjoyed their work or found their work meaningful (these are intrinsic motivators), non-engaged workaholics were more likely to work for extrinsic motivators such as money and status. Intrinsic motivation is associated with more optimism, effort, and persistence, whereas extrinsic motivation often instigates anxiety and undermines persistence, making failure more likely.

The proactive mentality that is characteristic of employees with intrinsic motivation may help them take action when they experience initial health complaints, whereas the anxiety and frustration that can accompany extrinsic motivation may make non-engaged workaholics more passive, such that they continue unhealthy work habits and eventually face substantial health risks. Thus, finding ways to promote intrinsic motivation in one’s work, whether through new projects or even a new job, may not only make you happier but also healthier.

Managers too can intervene by helping employees find intrinsic motivation; they can re-engage them in their work and provide more support. This can mean assigning employees challenging but feasible tasks, reducing red tape and other barriers, discussing their personal and professional growth, and providing them with ample resources to do their work, such as autonomy, feedback, and support. Managers can help hard workers develop stronger communication and time management skills, with tactics such as making a to-do-list each week, making a long-term goal list, differentiating between urgent and non-urgent tasks, and scheduling non-interrupted time for important tasks. Friends and family can also play a role by making sure that employees have emotional and tangible support at home.

Ultimately, the challenge for anyone is to identify a compulsive work mentality and prevent its consequences. Focusing on one’s engagement and ability to “switch off” will go a long way in helping employees feel happy at work and outside of it.