As a growing number of states legalize marijuana use, a leading pediatricians’ group is pushing for more education about pot's potential to harm young people's health.

"With the legalization there is now much more of a perception out there that marijuana is benign," said Dr. Seth Ammerman, co-author of the new report from the American Academy of Pediatrics. "For many adults who engage in moderate use it can be, but adolescents are not adults and it's a very different issue for them."

The report includes guidance for pediatricians, parents and young people.

"'Just say no' doesn't work," said Ammerman. "What is helpful is to have an open discussion about drug use, including marijuana." The report states that the potential effects of marijuana use range from cognitive and psychological issues to lung problems.

Prop. 64, approved by California voters last November, legalized recreational marijuana use for those over the age of 21. The new law seeks to protect young people: It sets aside some tax revenue from pot sales for education and treatment of substance use disorder, and it bans marketing "known to appeal primarily to persons below the legal age of consumption."

There is still much to be learned about the effects of sporadic and occasional marijuana use on adolescent brains, said Dr. Thomas Strouse, medical director of the Stewart and Lynda Resnick Neuropsychiatric Hospital at UCLA. However, "we know something about the effect of heavy use on the developing brains and that's pretty worrisome," he said.

Several studies have suggested a connection between psychosis and marijuana. Strouse said he sees young adults with psychotic symptoms associated with heavy marijuana use "every day" in his hospital. That does not mean that the psychosis was caused by marijuana, he said, because the individual may have been using marijuana to deal with the symptoms of a mental illness.

Among the American Academy of Pediatrics report's points: