Finding out your partner or spouse is cheating is among the most painful experiences you can have, but new research suggests that pain can reach far beyond emotional anguish. The study found that people who’ve experienced infidelity are more at risk of chronic health problems, and that these can continue even when they’re in a new, positive relationship.

Cheating in relationships is not rare, and there are lots of reasons that lead people to be unfaithful. Anyone who has ever gone through it knows how traumatic it can be, and how difficult it is to move on, but you may not have considered that such an experience could have the potential to cause physical harm too.

Drs Eunicia Hoy and Vincent Oh from the Singapore University of Social Sciences recently conducted a study to investigate the long-term health effects of infidelity. They used data from 2,579 US adults drawn from the Midlife Development in the United States (MIDUS) study, a nationally representative sample. All participants were cisgender, and a large majority were heterosexual. 

Two waves of data were compared, with approximately nine years between responses. The respondents were asked whether their partner had ever cheated, and were also asked to report long-term health conditions such as chronic migraine, sleep disorders, and lung problems. Other demographic data and information about participants’ family and friend support networks were collected as well. 

When the results were analyzed, they showed that people who had experienced partner infidelity were more likely to report chronic health issues than those who hadn’t, even when other factors were accounted for.

“The good news is that effect sizes between infidelity and chronic health were in the ‘small’ range. Such effect sizes do still suggest the potential for lasting harm with practical implications, but at the very least, the effects are not extremely large,” Oh told PsyPost. 

Perhaps surprisingly, having a strong network of family and friends, or having moved on to a more supportive relationship, did not appear to mitigate this association, Oh explained. “We hoped to find that, perhaps, other sources of social support would at least reduce the chronic health associations of being cheated on. This was unfortunately not the case based on our findings.”

In their paper, the authors propose that the emotional distress that infidelity causes may have a knock-on effect on people’s physical health, although they also recognize that this topic remains understudied. There is a smattering of other evidence in the literature about how relationship satisfaction can impact health, such as findings that married people may be less likely to develop dementia; equally, however, there are cases where ending a relationship can paradoxically make people feel better. No two relationships, and no two infidelity situations, are the same. 

This also speaks to a limitation of the study – the participants were only asked if they had ever been cheated on, and no further details of the circumstances were collected. As Oh explained to PsyPost, “[T]he conclusion is solely about whether an individual has been cheated on before, and whether this is associated with poorer chronic health.”

But it’s an interesting basis for further research, and does flag up the possibility that, in some cases at least, being cheated on can leave someone with health issues that last long after the ice cream has been eaten and the credits on the weepy movies have rolled.

The study is published in the Journal of Social and Personal Relationships.