According to Scottish researchers, people spread a story if it is about a person who is familiar to them and if it is a particularly "juicy" piece of information.
To reach this conclusion, researchers at Glasgow University and University of the West of Scotland asked participants to read fictional stories.
Nearly 100 popular celebrities, including US President Barack Obama and First Lady Michelle Obama, and David and Victoria Beckham, were involved in a number of false stories, such as getting pregnant, having a row in public, or being caught with drugs.
The celebrity and non-celebrity subjects were also placed in everyday scenarios such as shopping or getting coffee, the Scotsman reported.
Participants were asked to read the stories and tell scientists how likely they would be to share these stories with friends.
The results suggested that the preconceived view of a character and the predictability of a story regulated how likely someone was to gossip about a story.
"Intuitively, it is not surprising that we are more likely to gossip about familiar people and interesting stories. However, we are much more likely to gossip when a story unites a familiar person with an interesting scenario," explained lead researcher Bo Yao.
A key function of gossip may be to maintain our reputation system by receiving updates on the recent behaviour of our acquaintances.
People sometimes use gossip quite selfishly to enhance their own social status, the study noted.