New research confirms the benefits of 12-step support groups in recovery from alcohol use disorder; data on drug use is less conclusive.

The 2020 Cochrane Collaboration review of 27 rigorous studies (involving a total of 10,565 individuals with alcohol use disorder) showed that A.A. produces outcomes as good as or better than high-quality psychosocial intervention such as cognitive-behavioral therapy. The review also found that AA reduces health care costs. Many of the participants in the studies also reduced their use of illicit drugs, suggesting that the type of substance used does not rule out positive outcomes.

Another study from 2021 found that participation in 12 step groups predicts lower illicit drug and alcohol use, and fewer use-related problems in a large, diverse, sample of drug use disorder patients. The study found that benefits are limited by lack of long-term participation, but that greater attendance resulted in greater benefits. (Read paper here)

There are no comparable large-scale reviews studying outcomes for family members or people secondarily affected by substance use who participate in Al-Anon or other 12-step support groups, but research with smaller subject groups suggests better mental health outcomes with participation.