A fair number of men don't practice what they preach when it comes to sex. Ten percent of the men in a recent survey who called themselves straight reported having had sex with at least one man in the preceding year.

Investigators led by Preeti Pathela, DrPH, of the New York City Department of Health and Mental Hygiene questioned 4,193 participants and found that one out of 10 who said they were straight reported they had engaged in sex with at least one man in the past year, often referred to as "down-low" behavior. Seven out of 10 of those men were married.

Of particular concern was the finding that many of these straight men admitted they had not used condoms or been tested for HIV. They were less likely to do so than gay men who had engaged in sex with another man during the previous year, the researchers found.

In terms of demographics, a large proportion of the straight men who had engaged in sex with at least one man resided outside the Manhattan area. They tended to fall into a low income bracket or were relatively uneducated. Many were minorities or had been born outside the US.

Doctors may need to inquire not only whether a patient is heterosexual, gay or married, but also what his sex habits are in practice, the researchers noted, in order to correctly assess his risk of sexually transmitted diseases.

"Prevention messages should focus on the activities that pose risk ...," Pathela and colleagues advise, "and should not be framed to appeal solely to gay-identified men."