It is well known that obesity raises one’s risk of developing type 2 diabetes, heart disease, stroke, high blood pressure and certain types of cancer, among other health problems. But how does it affect one’s sex life? Leave it to the French to provide the answer.

In a study to be published online Wednesday in the British Medical Journal, researchers from the National Institute of Health and Medical Research in Paris and the London School of Hygiene and Tropical Medicine report that obese men and women have more health issues related to sex than people of normal weight. Using data collected during lengthy phone interviews with more than 10,000 French adults, they found that:

• Compared with women of normal weight, obese women were 30% less likely to have had a sexual partner in the previous year.
• Obese women in their late teens and 20s were three times as likely to have met a sexual partner online and twice as likely to have watched a pornographic movie.
• Among women in their late teens and 20s, obese women were four times more likely than normal-weight women to report an unintended pregnancy or an abortion.
• Perhaps this was because they were 70% less likely to use birth control pills and eight times more likely to rely on “less effective methods, such as withdrawal.”

As for the guys:

• Compared with men of normal weight, obese men were 70% less likely to have had more than one sexual partner in the previous year (but equally likely to have had at least one).
• Obese men were more than twice as likely than normal-weight men to have experienced erectile dysfunction in the previous year.
• Among men in their late teens and 20s, the odds of contracting a sexually transmitted disease in the previous five years were more than 10 times greater for obese men than for men of normal weight.

“The study lends a new slant to a familiar message: that obesity can harm not only health and longevity, but your sex life,” concludes an editorial that accompanies the study.

-- Karen Kaplan