Is hip-hop music ripe with references to substance use? Yes, according to a new study.

In fact, hip-hop was the leading genre of popular music that referred to substance use more than any other genre -- at least, from a study of the most popular songs of 2005.

According to a press release, a new research was presented at the American Public Health Association's Annual Meeting & Exposition in Washington, D.C. at the beginning of November, where it was concluded that 33% of the most popular songs -- or one in three songs -- of the aforementioned year had references to substance use. For the study, researchers analyzed 279 of the year's most popular songs according to Billboard.

The results ended in rap music leading the way with 77% of the songs referring to substance use, while country was 37%, R&B at 20% percent, rock at 14% and pop music at 9%.

Among the substances referred to in the music, alcohol and marijuana were the most frequently mentioned. And was commonly associated with partying, sex, violence and/or humor, and was most often motivated by peer/social pressure, sex, and/or money (for instance, through trafficking).

The majority of songs with substance use portrayed more positive than negative consequences of use.

"Previous research has shown that exposure to substance use messages in media is linked to actual substance use in adolescents," said Brian A. Primack, MD, EdM, lead researcher on the study. "That is why we need to be aware of exposures such as these, especially when they are associated with highly positive consequences and associations."

For more information on the study, visit the American Public Health Association's website at APHA.org.