While around 54% of American women are engaged in some kind of paid labor, 66% of men also have paying jobs, according to the Department of Labor. It would make sense, therefore, that men work longer hours than women. When unpaid labor is factored in, however, it is clear that women work at least an hour longer than men on average every day.

A study by the World Economic Forum, while women work around 4 hours a day at paid labor, almost 5 hours is spent in unpaid labor – such as childcare, family care, and domestic work. Men, meanwhile, tend to work around six hours a day at paid labor, with only 90 minutes a day contributed to unpaid labor.

Another study in Australia suggests that it is the push towards gender quality that is creating these longer hours for women. When women primarily did domestic labor and men worked outside the home, the hour balance was more equivalent – though it’s worth noting that in the lower classes, women have frequently both worked outside of the home and inside of it; much domestic labor was pushed onto children, especially young girls.

All this extra work is taking a toll on women’s overall health in many different ways.

Heart Health

Doctors have known for years that working for many long hours put people at risk for problems with their hearts. The European Society of Cardiology published a 2010 study regarding this topic. People who worked three hours longer than a typical 7-hour day were at a 60 percent higher risk for heart disease, angina, and non-fatal heart attacks. According to one of the doctors working on the study, this risk was separated out from other risks to heart health, including obesity, smoking, or high cholesterol. Risk of stroke also increases in older workers.

Increasing Depression

When women work significant amounts of overtime, such as 11 to 12 hour days regularly, are at double the risk of a major depressive episode. While this overtime may seem excessive to the average office worker, at least on a regular basis, teachers and nurses work these sorts of hours often; these professions are often dominated by women, again putting women’s health particularly at risk.

Excessive Drinking

Working long hours correlates with risky drinking, according to another study. The study authors defined risky drinking behavior as more than 14 drinks a week for women and 21 drinks a week for men. Excessive drinking is associated with many other health conditions, including heart disease, liver disease, stroke, and mental health disorders. 48 hours a week is considered long hours; many people on salary are expected to put in approximately 48 hours regularly.

Excessive drinking is a concern because it can aggravate all of the other conditions we’ve already talked about. The belief is that people working long hours tend to drink alcohol to relieve stress after work and to relax enough to sleep. But drinking can cause cyclical problems, and can lead to addiction.

Changing Demographics

According to recent survey data, even when men and women both full time, women tend to put in more hours during the week. Women estimate that they spend more than 2 hours a day on household chores; men put in around 90 minutes. While those numbers are similar, they add up over a week, especially when women are also getting paid less for the same amount of work.

Inefficient Working

We often think that more work is better than less work, but the research doesn‘t support that conclusion at all. A study from Stanford suggests that above 40 hours a week, the quality of work quickly decreases, to the point that someone working around 70 hours a week doesn’t actually get more done than a person working around 50 hours a week. But all those extra hours are bad for health in all the reasons listed above.

Put simply: too many hours increase both physical and mental stress. We often think of this simply in terms of being tired at the end of a long day, but the effects accumulate over time. Hearts work too heart, blood pressure and cholesterol increase, and the risk of depression and heavy alcohol use increase. Depression and alcohol use make it harder to make the healthy lifestyle changes that mitigate the risks of stress on the body.

What is the solution for all these extra hours? It may not be as simple as just shifting the balance of hours that men and women work inside and outside the home. For example, these uneven hours may, in part, be a reflection of how women are more likely to work part time. This may be due to their family’s need for childcare, or because it’s almost too expensive for a woman to work full time. But breaking down gendered stereotypes, both in the home and in the workplace are likely to improve the health of all genders.