The more social circles or Facebook friends a person has, the more likely social media can become a source of stress, Scottish researchers say.

The more groups of people in someone's Facebook friends, researchers at the University of Edinburgh Business School reported, the greater the potential to cause offense, particularly if employers or parents are included.

Stress rises when users present a version of themselves on Facebook that is unacceptable to some of their online "friends," the researchers said.

Some 55 percent of parents follow their children on Facebook, they said, while more than half of employers have admitted to not hiring someone based on the applicant's Facebook page.

"Facebook used to be like a great party for all your friends where you can dance, drink and flirt," Edinburgh researcher Ben Marder said. "But now with your Mum, Dad and boss there, the party becomes an anxious event full of potential social landmines."

The researchers surveyed more than 300 people on Facebook, mostly students, with an average age of 21.