Lifestyle and exercise

Casual sex can boost self-esteem

“Casual sex IS good for self-esteem – but only if you're a 'physically strong, narcissistic male’,” says the Mail Online, somewhat inaccurately.

The paper seems to have misread the results of this study of sexuality among US college students, which followed them over a nine-month period.

The researchers were interested in three factors:

  • Their sexual activity – particularly whether they had penetrative sex with people they were not in a relationship with.
  • Self-reported emotional states – in terms of anxiety, depression, self-esteem and life satisfaction, and what the researchers described as:
  • “Sociosexual orientation inventory” – this is a type of scoring system, based on questions such as “do you think sex without love is OK?”; these questions were designed to assess their acceptance (or not) of promiscuous sexual behaviour

It found that casual sex enhanced overall wellbeing – but only in people who scored highly on the sociosexual orientation inventory.

The main finding, which could be described as blindingly obvious, is that people who like having casual sex find having casual sex rewarding.

Where did the story come from?

The study was carried out by researchers from Cornell University and New York University. It was funded by various non-profit organisations in the US.

The study was published in the peer-reviewed journal Social Psychological and Personality Science.

The tone of much of the UK’s media reporting of this study is moralistic, puritanical and, arguably, sexist.

There seems to be an assumption that any woman who engages in casual sex is doing so because they are emotionally damaged in some way. This includes the Metro’s strange statement: “you can stop having a mini meltdown and inhaling a whole bottle of wine every time you have a one night stand”.

The concept that women have casual sex because they just enjoy having sex seems to be alien to the UK media.

The Mail Online’s report that those who got the biggest boost were “sexist, manipulative, coercive and narcissistic men” was not supported by this research. 

Still, the Daily Mirror should be congratulated for including the useful advice that “if you want casual sex to remain a healthy activity, always use protection”, such as a condom, which is the best protection against unwanted pregnancies and sexually transmitted infections (STIs).

What kind of research was this?

This was a longitudinal study of 371 single, US students, with the researchers aiming to examine whether someone’s “sociosexuality” was a factor in a person's degree of wellbeing after having casual sex.

Sociosexuality is a measure of the willingness to engage in sexual activity outside of a committed relationship.

Individuals with a low (or restricted) sociosexual orientation are less willing to engage in casual sex.

Those who have a more unrestricted sociosexual orientation are more willing to have casual sex, and are more comfortable engaging in sex without love, commitment or closeness.

Casual sex is defined as sexual behaviour occurring outside of committed romantic relationships.

The authors say that casual sex is common among contemporary college students. Research results on the effects of casual sex are inconsistent, indicating both positive and negative effects. They suggest this inconsistency may be due to the presence of individual “moderators”, such as personality. They hypothesised that sociosexuality may moderate the link between casual sex and psychological wellbeing

In other words, those with “restricted” sociosexuality experience lower wellbeing, but unrestricted individuals experience higher wellbeing following casual sex, compared to not having casual sex.

Women have consistently been found to have lower sociosexual desires than men, according to the researchers.

They also say that acting “authentically” according to one’s personal desires and values may also be an important factor as to whether casual sex affects wellbeing.

They tested their hypothesis in a sample of college students on a weekly basis over 12 weeks and 9 months.

Casual sex was defined as any penetrative sexual activity (vaginal, oral or anal) occurring outside of established romantic relationships.

What did the research involve?

In 2009/10, researchers invited 6,500 students to participate in a longitudinal study of sexuality.

The students were sent a questionnaire measuring their propensity towards casual sex, with questions about their sexual behaviour, sexual desires and attitudes towards sex. A copy of the questionnaire is available online.

Items could be answered on a 9-point scale, from 0 to 20 or more. For example, they were asked how often they have spontaneous fantasies with someone they have just met; answers could range from “never” to “at least once”. They were also asked if “sex without love is OK”, with their answers ranging from “strongly disagree” to “strongly agree”. Higher scores indicated greater sexual unrestrictiveness.

A sub-sample of the students were then invited to participate in a three-month online weekly diary study of their sexual experiences.

In this weekly survey, participants were asked how many different partners they had sexual encounters with each week. 

They were asked further details of the sexual behaviours they engaged in and the status of the sexual relationships – i.e. whether they were casual. 

Those with sexual experiences were also asked to think of their most memorable sexual encounter that week and report how much they experienced "feeling genuine/true to myself" and "being in control of what was happening" during this encounter on a scale of one (not at all) to seven (a great deal).

At a nine-month follow-up period, participants reported on the number of one-night stands and longer casual partners (e.g. friends with benefits) they had engaged in oral, vaginal or anal sex with since the beginning of the study.

The students psychological wellbeing was assessed at baseline, at follow-up and weekly.

Using validated scales, researchers measured depression and anxiety, self-esteem and life satisfaction.

They analysed the results to see whether students' sociosexuality had any moderating effect on their wellbeing after casual sex. 

They also tested for gender differences, and whether the moderating effect of sociosexuality applied to both one-time and longer casual encounters (e.g. so-called “friends with benefits”).

There were 872 (13.4%) students who completed the baseline questionnaire. The researchers excluded anyone aged over 24, engaged, married or in a long-term committed relationship. After exclusions, the final nine-month sample came to 371, and the final subset of students who participated in the weekly analysis was 230.

What were the basic results?

The researchers report that sociosexuality moderated the effect of casual sex on a person's on a weekly basis. This was also the case at three and nine months. Sociosexually unrestricted students typically reported higher wellbeing after having casual sex, compared to not having casual sex, but there were no such differences among sociosexually restricted students.

Few differences between men and women were found.

Other findings were as follows:

  • Out of a total of 2413 weekly reports, 204 (8.5%) reported casual sex; 90% of these involved only one partner (there was a maximum of three casual partners during the study).
  • 35% of students reported at least one week with casual sex, with the percentage similar in both sexes.
  • The average proportion of weeks with casual sex was 0.09% per participant.
  • Higher sociosexuality was linked to a higher likelihood of engaging in casual sex, but gender was not significant. 

How did the researchers interpret the results?

They say the effects of casual sex depend on the extent to which this behaviour “is congruent with one’s general personality and reproductive strategies”.

Those whose personalities are oriented towards casual sex report lower distress and higher “thriving” following casual sex.


As the authors point out, a weakness of this study is the low response rate, which might have resulted in bias: the students who chose to take part may have been more interested in sex to begin with. 

Another limitation is the very low rates of casual sex reported, which means the study could be underpowered.

It is also possible that its reliance on the self-reporting of sexual encounters may have led to unreliable results, with participants playing down – or up – the number of casual encounters they had.

The study did not control for other factors that may affected students' wellbeing, including friendship, relationship, academic or financial problems.

That said, the study’s conclusion – that the effect of casual sex on wellbeing depends on one’s attitudes towards it in the first place – makes considerable sense, and is hardly surprising.

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