Teens and young adults who engage in frequent casual sex are at greater risk of depression and even suicidal 
thoughts, according to new research.
A study published in the Journal of Sex found that poor mental health and casual sex contribute to each other over time among teens and young adults.
According to the research, carried out at Ohio State University, teens and young adults who had casual sex were more likely to be depressed later on.
The researchers also found teens who showed symptoms of being depressed were more likely than others to have casual sex.
The lead author of the study, Sara Sandberg-Thoma said that a question about whether casual sex caused depression, or whether people with depression tended to have more casual sex had always been present.
“This study provides evidence that poor mental health can lead to casual sex, but also that casual sex leads to additional declines in mental health” Sandberg Thoma said.
According to the study, the findings apply to both men and women alike.
Claire Kamp Dush, assistant professor of human sciences at Ohio State, said the results “suggest that poor mental health and casual sex are linked, whether you’re a man or a woman.”
Ten thousand adolescents from 80 high schools and 52 middle schools in grades 7 through 12 were interviewed. The teens were then interviewed again when they were aged 18 to 26.
They were surveyed about their romantic relationship experiences as well as depressive symptoms and thoughts of suicide.
“Casual sex” was defined in the study as having sex with a partner that one was not “dating.”
Overall, 29 percent of the respondents—33 percent of men and 24 percent of women—reported engaging in any casual sexual relationship.
The participants who reported having casual sexual relationships when they were young adults were more likely to have thoughts of suicide or more depressive symptoms as teens.
Researchers found that each additional casual sexual relationship increased the odds of suicidal thoughts by 18 percent.
However they also found that although casual sex was linked to suicidal thoughts, it did not have any effect on depressive symptoms.
It is thought that this may be because depressive symptoms fluctuate during adolescence and it is hard to capture an accurate reading when it is only measured twice.
‘Just because a person does not indicate depressive symptoms in one survey is not always proof that he or she is doing OK,’ said Dr Kamp Dush.
‘We need to look at multiple indicators of mental health, including suicidal thoughts.’
‘The goal should be to identify adolescents struggling with poor mental health so that we can intervene early before they engage in casual sexual relationships,’ said Sandberg-Thoma.
‘Young adulthood is a time when people begin to learn how to develop long-term, satisfying and intimate relationships,’ said Dr Kamp Dush.