When Dr. Evil stole Austin Powers's mojo, the sex-crazed British spy became "shagless." If you're overweight and feeling a little bit like Austin, and even a Barry White CD playing on the stereo doesn't get you in the mood, the extra pounds could be the problem. Researchers at the Duke University Medical Center conducted a survey to find out what effect, if any, obesity has on libido.

What the researchers wanted to know: Does obesity interfere with the quality of a person's sex life?

What they did: The researchers recruited 1,210 people from the community and from the Duke Diet and Fitness Center to answer a 31-item questionnaire. Of the participants, 928 were considered obese, and 506 of those were seeking treatment at Duke. Obesity is defined by a body mass index (BMI) of 30 or greater. The average BMI of the treatment-seekers was 41, and that of the non-treatment-seekers was 40. The remaining 282 participants in the survey had an average BMI of 22.

What they found: Obese people were 25 times as likely to report dissatisfaction with sex as the normal-weight people. About 65 percent of treatment-seekers and 41 percent of obese people who weren't getting treatment said they had problems in at least one of four areas: lack of sexual enjoyment, lack of sexual desire, difficulty with performance, and avoidance of sexual encounters. Only 5 percent of those in the normal-weight group had any problems in these four areas. About 40 percent of treatment-seekers said they avoided sex altogether, while 24 percent of non-treatment-seekers and just 2.5 percent of the normal-weight participants avoided sex. According to the results, women had more problems than men in both weight groups.

What it means to you: Research has already shown that obesity can lead to a variety of health problems, including heart attacks and diabetes. And now it looks as if obesity has an effect on behavior in the bedroom as well. For some, losing weight may help them get their mojo back.

Caveats: The results of this study were presented at the annual meeting of the North American Association for the Study of Obesity, so this study has not been peer reviewed. Also, consider that the study was funded by Duke Diet and Fitness Center.

Find out more: Learn more about obesity from the Centers for Disease Control and Prevention.

Figure out your BMI using our calculator.

Tips for healthful ways to lose weight from the Food and Drug Administration

A study shows losing weight helps with erectile dysfunction.

Read the press release online: http://dukemednews.org