It has long been associated with guilt and heartache, but a new study suggests casual sex can have a positive effect - for some people.
US researchers found that in those who were up for it, casual sex was associated with higher self-esteem and life satisfaction - and lower depression and anxiety.
Generally speaking, those who got the biggest boost were "sexist, manipulative, coercive and narcissistic men".
The results were gathered by recruiting 370 students who were surveyed for nine months about their sexual feelings and behaviour and overall wellbeing.
They were asked questions about their views on casual sex, how many people they had slept with only once and their level of sexual desire.
Those who had indulged in and enjoyed casual sex were defined as being "sociosexual".
These people (42 per cent of the group) reported better rates of self-esteem and lower rates of depression than those who hadn't got together with anyone over the previous nine months.
One theory is that high sociosexuality may both buffer against any potentially harmful consequences of casual sex and allow access to its potential benefits, the researchers wrote.
Lead researcher Zhana Vrangalov, of Cornell University, told Pacific Standard: "This study certainly seems to suggest that casual sex can be a good thing for people who are open to it, desire it, and have positive attitudes towards it."
But she added that safe sex and not being too drunk could be key to this, as much of the guilt that follows a one-night stand relates to being too drink and fear of pregnancy or catching a sexually transmitted infection.
Dr Vrangalova, a professor of psychology at New York University, also defined key character traits of people who constantly want casual sex.
"They are generally extroverted, sensation-seeking, impulsive. avoidantly attached males, who also invest less in romantic relationships and are more likely to have cheated on a romantic partner," she told journalist Ryan Jacobs.
"Among men, they are also more likely to be physically strong, and especially among college men, also more sexist, manipulative, coercive and narcissistic.
"They also tend to be unconventional, attractive, [and] politically liberal."
However she stressed the findings did not suggest people prefer casual sex over that in a relationship.
Much of the previous research into casual sex has focused on the psychological damage it may cause.
A study from Ohio State University found that casual sex can cause depression and can even lead to thoughts of suicide.
Researchers interviewed around 10,000 people and found that teenagers with depressive symptoms were more likely to engage in casual sex.
Each additional casual sexual relationship also increased the odds of suicidal thoughts by 18 per cent.
And last year scientists at Emory University reported casual sex is more satisfying for men - and that women are twice as likely to orgasm when having sex as part of a committed relationship.
- Daily Mail