Cigarette smoking is pervasive in movies, according to a National Cancer Institute report, which said tobacco marketing and showing smoking in movies promotes smoking among young people.

The report said smoking is seen in at least three out of four contemporary box-office hits. It also said identifiable cigarette brands appear in about one-third of movies.

One of the recommendations suggested by the editors of the report is to put anti-tobacco advertisements before films "to partially counter the impact of tobacco portrayals in movies."

"There is now incontrovertible evidence that marketing of tobacco, and the depiction of smoking in the movies, promote youth smoking and can cause young people to begin smoking," Barbara Loken, professor of marketing at the Carlson School of Management and one of the report's five scientific editors said in a news release.

Last month, six major movie studios — Paramount Pictures, Sony Pictures, Twentieth Century Fox, Universal Pictures, Walt Disney Co. and Warner Bros. — agreed to place anti-smoking announcements on the DVDs of all movies with youth ratings (PG-13 or below) that depict smoking, Reuters reported.

The agreement does not include youth-rated movies in theaters.

The Associated Press contributed to this report.