Talking about someone behind their back might sound malicious or dishonest, but it doesn't have to be. If the information being shared is based on truth, it can actually have a positive effect on our relationships with others, according to new research.

The findings are based on a mathematical model of gossip that recently won the Ig Nobel Prize, a satiric award designed to first make people laugh and then make them think – much like gossip itself.

Whispering about others is usually frowned upon, but this sly form of communication is also a staple of human interaction. Given how widespread gossip appears to be, there's a strong chance that it is somehow useful.

In fact, a growing body of research demonstrates some of the important social functions of gossip.

For instance, it could be a good way to judge another's trustworthiness. If someone shares false information about a third party for personal benefit, the listener might be able to detect the lies and come to distrust the liar – a form of social punishment.

Alternatively, if someone shares true information about a third party, this could improve trust between individuals, thereby promoting and sustaining group cooperation and teamwork.

Using a simplified mathematical model, an international team of researchers attempted to explore when gossip is likely to be honest and or dishonest, and how those scenarios ultimately play out for all those involved.

The model was mainly put together by Paul van Lange from Vrij Universiteit Amsterdam, Szabolcs Számadó from the Hungarian Academy of Sciences, and Junhui Wu from the Chinese Academy of Sciences in Beijing.

Together, they simulated gossip as a triangle. One corner base of the triangle is the gossiper, the other corner base is the recipient, and the top of the triangle is the third person who is being talked about while not present.

This model was then used to explore four distinct social interactions using four games that captured possible repercussions of gossiping.

In other words, whether the exchange benefited the person who heard the gossip or whomever it was about, or if it was costly to either one of them, or both.

With the modeling, the researchers tested their hypothesis: that gossipers would choose to spread honest truths or falsehoods to maximize their own benefit without costing their reputation, all the while weighing what connection they had to the other two people involved.

In general, gossipers decided to be honest when they shared a goal with the other two parties, making their success (or failure) intertwined.

But when their goals were mismatched with the recipient and target of their gossip, they were much more likely to spew lies.

"For example, you may be competing with a co-worker for a prized promotion, where only one of you can get the job," explains supporting author and metascientist Leo Tiokhin from Eindhoven University of Technology in the Netherlands.

"In such situations, people are negatively interdependent: one person's failure means the others' success. Such situations can be expected to lead to dishonest gossip to harm co-workers, or honest gossip when the content of the gossip is already negative."

The models used by researchers are only theoretical and don't reflect the complexity of social interactions because they rely on several assumptions. For instance, the recipient of gossip is always assumed to believe what they are hearing.

In addition, the gossiper always knew if others around them were likely to cooperate or not.

"These assumptions were made for tractability, and they could certainly be modified in future extensions of our work," says Tiokhin.

Using game theory, researchers found evidence that gossipers can make optimal decisions about whether to lie or not, depending on the situation and how it suits them.

Some studies support this idea. For instance, some research suggests that gossiping about rivals is more likely to be dishonest, whereby the gossiper tends to falsely describe the other person's actions or intentions when those intentions are actually good.

On the other hand, other studies have found gossiping about loved ones is more likely to be positive and might make an interconnected group even more close-knit.

"[T]he field is still in the early stages of understanding the situational underpinnings of individuals' strategies to share honest or dishonest gossip," the authors admit.

"We show that honesty is determined by the marginal cost/benefit resulting from honest or dishonest gossip."

The study was published in Philosophical Transactions of the Royal Society B Biological Sciences.