The next time you're feeling overstressed, think twice before blaming work. 

While the conventional wisdom suggests that work is a major source of stress for Americans, a recent Penn State study found that both men and women have significantly lower levels of stress at work than at home.

The researchers analyzed 122 randomly selected individuals over the age of 18 and measured stress by looking at subjects' average cortisol levels, a major marker of stress.

"There has been a lot of research over the years that shows that working is good for you, that people who work have better physical and mental health than those who don't," says Penn State professor Sarah Damaske. 

There are a number of reasons why professional work can be less stressful than chores or other work done at home:

1. Paid work is satisfying. Research shows that women across a wide range of occupations, from COOs to employees at Wal-Mart, derive significant satisfaction from doing their jobs well.

2. Paid work is more culturally valued in society. People get praised for their professional work. When was the last time someone complimented you for doing the dishes?

3. Work at home can be monotonous and repetitive. When you finish a task at work, you're done with it and you move on. Laundry and the dishes keep coming back.

"The big finding that everyone's really excited about is this cortisol finding, but one of the other big findings is that people are much more stressed out on work days than on the weekends," Damaske says. "The combination of the two suggests that work is good for you, but that combining work and family can be stressful."