Chances are you've thought about unfriending someone before and maybe you've even done the deed.

A study from the University of Colorado finds 40% of of respondents would avoid real world contact with someone who unfriended them on Facebook.

The researchers say the main reasons people might remove someone from their friends list include posting unimportant material, posting religious or political rants, making sexist or racist remarks or posting boring things.

The study was based on 582 responses gathered using Twitter.