Kids who abstain from marijuana use are not emotionally or socially troubled, whereas those who use alcohol or other drugs while alone tend to suffer a range of psychosocial and behavioral problems, according to research from the RAND Corporation.

Research from the 1990s by Shedler and Block indicated that youth who abstain from marijuana use lacked social skills and were more anxious than those who experimented with the drug, who were found to be better adjusted emotionally and socially. The findings suggested that drug experimentation was a normal part of development.

However, the latest RAND research disputes these findings, saying that abstainers are not maladjusted and had better outcomes as young adults than experimenters, engaging in fewer socially deviant behaviors. "Experimentation with drugs has sometimes been viewed as developmentally appropriate and adaptive," according to RAND. "In contrast, the RAND results indicate that youth who experiment with marijuana are worse off in many respects than those who abstain throughout their teenage years. This insight helps the drug-prevention community put into perspective the conflicting conclusions from prior studies about marijuana use and its consequences."

"Marijuana abstainers do well, solitary users do poorly, and kids who use marijuana only in social settings are in between," according to a RAND press release on the research, which was based on a review of more than 20 years of data from the RAND Adolescent/Young Adult Panel Study.

RAND researchers called young solitary substance abusers "an overlooked, at-risk group." Research showed that while only a small percentage of youths used alcohol, tobacco and other drugs while alone, they were more at risk of heavy substance abuse, got into trouble more, were less likely to talk to their parents about their problems, and performed more poorly in school than their peers.

"Contrary to what might be expected, these youth are not loners," RAND noted. "They are socially active teens who spend more time hanging out with friends, going to parties, and dating than do youth who limit substance use to social settings. Popularity with peers may help compensate solitary users for their poorer academic track records and behavioral problems in the short term."