No increase of consumption among young adults in California
Following the legalisation, a study has shown that there was no increase in consumption with young adults.

Adult cannabis use in California has brought some changes to the state, including easier access to needed medicine and a thriving cannabis tourism scene. However, there has been no significant increase in cannabis use among young adults since legalization began. The recently published study, published in the journal Addictive Behavior and conducted by the University of California at San Diego, looked at cannabis use in a group of 563 young adults, all ages 18 to 24 years old. All adults lived in California in the years prior to cannabis legalization, and trends were monitored by their activity throughout the study. The study was originally conducted because of concerns about cannabis use among adolescents and young adults. In their abstract, the researchers wrote that adolescent use was a problem because of the chronic health risks associated with cannabis use and concerns about an increase in tobacco and nicotine use due to legalization. They included this because no other study had looked at this link before their, and to see if the frequency of cannabis use would increase with recreational sales. They also assumed that more cannabis legalization would lead to more cannabis and nicotine use.
