Laughter is the best medicine — that's a phrase we hear quite often. The act triggers the release of feel-good hormones, promotes stress reduction, and improves the functioning of the immune system and various organs.

But is laughter among the key factors which determine how much a romantic relationship thrives? It certainly could be, according to a new study from Martin Luther University Halle-Wittenberg (MLU) in Germany.

When anyone is asked about the kind of person they would like to date, you may have noticed that "someone with a great sense of humor" is a very common answer. The new findings suggest that the extent to which they share humor-related traits may end up affecting relationship satisfaction.

Some people may dislike or fear being laughed at, interpreting it as something derogative, according to MLU psychologist Professor René Proyer. But others tend to enjoy making people laugh, even if it means making themselves a subject of ridicule. Another trait, of course, is to enjoy the act of teasing and laughing at other people.

"These three characteristics are personality traits that can occur at the same time, to varying degrees and in different combinations," said Proyer. For example, a person might love laughing at others but tends to feel hurt or annoyed when others laugh at them. 

As part of the study, over 150 straight couples were recruited to take part in online interviews with psychologists from MLU. Each partner separately answered questions about themselves and their relationship.

"We found that partners are often alike with regard to their individual characteristics and also their profiles," said Kay Brauer, who conducted the study along with Proyer. So if couples handled laughter — or being laughed at — in similar ways, it tended to have a positive effect. "Women reported more often that they tended to be satisfied with their relationship and felt more attracted to their partner. They and their partners also tended to be equally satisfied with their sex life."

This was reversed in couples who did not have similar ways of handling laughter. Men, in particular, felt less satisfied with their sex life if their partner was afraid of being laughed at.

There was an interesting exception where this interdependence was not found in couples who liked to ridicule others together. In fact, couples who shared this trait actually seemed to argue more. "That is hardly surprising, considering that these people often go too far and make derisive comments which can then lead to an argument," Brauer said.

So in some cases, this could play a role in fueling emotional mistrust and sexual dissatisfaction, indicating that the relationship may not last. But the researchers add that the handling of laughter does not completely suffice as a determinant for every couple out there. 

Nevertheless, noting whether one of the partners has a fear of being laughed at could be useful information in the context of couples therapy or relationship counseling.