Approximately five million people in the U.S. attend addiction self-help groups like Alcoholics Anonymous and Narcotics Anonymous, according to a new report from the Substance Abuse and Mental Health Services (SAMHSA), Reuters reported Nov. 24.

The study, which was based on data from a survey of 135,672 Americans over the age of 12 and conducted in 2006 and 2007, showed that about 45 percent of those attending self-help groups reported that they abstained from drugs and alcohol in the month before the survey, and more than 30 percent said they participated in formal addiction-treatment programs in the past year.

"The data reinforces the fact that participation in self-help groups is associated with abstinence and recovery," said Stephen Wing, SAMHSA's associate administrator for alcohol policy.

Of the 5 million people attending self-help groups, roughly two-thirds were male, and 80 percent were over the age of 25. SAMHSA did not have data on whether attendance at self-help groups had increased. About 22 million Americans meet the definition for substance abuse.