In your social circle there's probably at least one guy who's had intercourse with a sex worker.
According to a new study of over 6,000 British men, one in 10 say they have paid for sex. In addition, 3.6% of the men surveyed admitted going to prostitutes in the past five years.
Single men aged 25 to 34, in managerial or professional occupations and those with high numbers of sexual partners, were the most likely to say that they had paid for sex.
"The picture that emerges does not necessarily fit the stereotype of the lonely older man," said lead scientist Dr Cath Mercer, from University College London (UCL).
"In fact, men who pay for sex are more likely to be young professionals with many unpaid sexual partners. Many report other hedonistic and risky behaviours including heavy drinking and drug taking."
The findings come from the third National Survey of Sexual Attitudes and Lifestyles (Natsal), conducted between 2010-2012 by researchers from UCL, the London School of Hygiene and Tropical Medicine and NatCen Social Research.
A total of 6,108 men aged 16-74 answered questions about paying for sex in a computer-assisted self-interview.
The study focused on men as the proportion of women who reported paying for sex was only around 0.1%.
Men who paid for sex reported an average of 31.6 lifetime sexual partners - more than twice the average for the male population.
They were also more than twice as likely as average men to have been diagnosed with a sexually transmitted infection in the past five years.
Men who used prostitutes made up 15.6% of all reported STI diagnoses in male population.
"Men who pay for sex are evidently at high risk of infection, but this does not necessarily mean that the STIs are spread through their paid sex," Dr Mercer added.
"Instead, we found that these men report engaging in other risky sexual behaviours, such as having concurrent - or overlapping - partners, and so should be considered a core-group for sexual health interventions and services."
Among men who reported ever having paid for sex, 62.6% had done so outside the UK at least once - most commonly in Europe and Asia.
This may be driven by "hotspots" such as Amsterdam and Bangkok, said the researchers.
"Paying for sex may seem more permissible abroad, at a place removed from the day-to-day lives of most men," Dr Mercer added.
"Paid sex can also be more readily available in certain areas so if men mention to their health professional that they will be travelling to destinations known for sex tourism, and especially those where the prevalence of sexually transmitted infections and HIV is high, then it would be opportunistic to have a conversation about safe sex."
The research is published in the journal Sexually Transmitted Infections.