If the ads in magazines seem to be getting sexier, it's not your imagination. A new study has revealed that the number of ads using sex to sell products nearly doubled over a 20-year period.

Tom Reichert, a professor of advertising and public relations at the University of Georgia, and his colleagues analyzed more than 3,000 ads published in various magazines -- from Playboy to Time -- from 1983 through 2003, finding that the percentage of ads featuring sexy models alone or engaged in steamy behavior with another model rose from 15 to 27 percent.

Which ones were the sexiest during the two-decade study period? Health, hygiene and beauty products, which used sexual imagery in more than a third of their ads. Drugs and medications, including weight-loss supplements, weren't far behind.

These days, clothing, alcohol, entertainment and beauty companies rely on sexy ads far more than they did in years past, and not surprisingly, female models are used in those ads nearly four times as often as male models are.

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