Twentieth Century jazz musicians like Cab Calloway or Mezz Mezzrow, who were singing about drug use three-quarters of a century ago, won't exactly be rolling over in their graves, but research results released last week show that contemporary music is replete with drug references, and most of them are positive.

Researchers at the University of Pittsburgh School of Medicine examined 297 songs that made it to the top of the Billboard charts in 2005 and found that 93 (33%) of them portrayed drug or alcohol use. Some 86% of hit rap tunes had drug references, followed by 37% of country tunes (presumably mostly alcohol references), 29% of R&B/Hip-Hop songs, 14% of rock songs, and 12% of pop songs.

Nearly one-quarter (24%) of drug use references were to alcohol, 14% were to marijuana, and only 3% were to tobacco. Some 12% of references were to drugs the researchers could not identify.

In the songs, people took drugs for various reasons, including peer pressure (48%), sex (30%), money (25%), or mood management (17%). Apparently, as in real life, people in songs took drugs for multiple reasons.

Drug use was commonly associated with partying (54%), sex (49%), violence (29%), and humor (24%). Only 4% of songs examined contained anti-drug use messages, one referred to setting limits, and none portrayed people refusing to take drugs. Of those songs that mentioned drug use, more than two-thirds (68%) were positive.

"We're learning that media affects a lot of different health behaviors," said assistant professor Dr. Brian Primack who headed the study. "Tobacco in movies, for example, is now known to lead to smoking. We started realizing adolescents are exposed to two and a half hours a day of music. What's in the music?"