WebMD Health News
July 7, 2011 -- Being very thin or fat appears to increase the odds that a man will experience some kind of sexual difficulty, but the same may not be true for women, a new study shows.
The study, a survey of more than 5,500 adults in Denmark, finds some surprising and complicated associations between lifestyle factors and sexual health.
In men and women, for example, body size -- being either too thin or obese -- appears to be related to the risk of having sexual problems. For men, those extremes increase the risk. Women in those ranges, on the other hand, appear to have less sexual difficulty.
The study shows that being very thin is associated with 22 times the risk that a man will experience some kind of persistent sexual dysfunction, including erectile dysfunction (ED), inability to orgasm, premature ejaculation, and pain with sex, compared to men who are normal weight.
Similarly, men with very large waists, over 40 inches, had a 71% increased risk of having some kind of sexual trouble compared to men who had a waist size under 37 inches.
“What I found interesting was that the number of men who were underweight, or had low BMI [body mass index], had various elevated risks for sexual difficulties,” said Edward O. Laumann, professor of sociology and an expert in human sexuality at the University of Chicago. He was not involved in the current research.
He says having a large waist and a high BMI, which is also associated with health conditions like heart disease and diabetes, has long been known to be associated with an increased risk of sexual dysfunction in men.
Understanding why having a low BMI might also increase the risk is “less straightforward to figure out” and will require more research, he says.
Being underweight appeared to cut a woman’s chances of having sexual difficulties in half compared to a normal-weight, sexually active woman.
And obese women, with BMIs over 30, had 70% less chance of experiencing some kind of sexual dysfunction than their normal-weight counterparts.
Sexual problems tracked among women in the study including vaginal dryness, inability to orgasm, pain with intercourse, and vaginismus -- involuntary spasms that tighten or close the vagina.
“The differences between men and women with respect to sexual dysfunction were surprising,” says study researcher Morten Frisch, DSc, associate professor at the Staten Serum Institute in Copenhagen, Denmark. “There may be a plausible explanation. Women who experience trouble may quit having sex altogether while men may continue, particularly into the older ages.”
Among other surprises in the study for women: Those who reported using marijuana in the last year were about three times more likely than those who did not to report being unable to orgasm.
And women were intense exercisers and competitive athletes were more than four times more likely than those who were light exercisers to report experiencing vaginismus.
“People know very well that these lifestyle factors are not good for their health in terms of heart disease and cancer and other things. Nevertheless, there is a continued consumption of these drugs and unhealthy lifestyles and they affect sexual health as well as physical health,” says Frisch.
The study is published in the Journal of Sexual Medicine.
