Eight years after legalization, cannabis use in California has not increased

Contrary to expectations, the launch of the legal recreational cannabis market in California has not led to a sustained increase in consumption. According to a new study published in the Journal of Cannabis Research, the proportion of adults who use cannabis has remained virtually unchanged since the adult cannabis market opened in 2018.

What has changed, however, is the way Californians consume cannabis: edibles are gaining popularity, while smoking continues to decline.

Cannabis use has remained remarkably stable since 2018

California was one of the first U.S. States Set to Legalize Cannabis for adult use after voters approved Proposition 64 in 2016. Retail sales officially began in early 2018, raising questions about whether easier legal access would lead to a significant increase in consumption.

Cannabis use in the past year stood at 22.1% of adults in 2017, the year before licensed retail stores opened. By 2024, that figure had risen to 23.5%, a difference that researchers deemed statistically insignificant.

A similar trend emerged in consumption during the previous month. Consumption rose from 14.5% in 2017 to 17.7% in 2018—coinciding with the opening of the legal retail market—before gradually declining. By 2024, consumption during the previous month had fallen to 15.4%, returning to nearly the same level as before the stores opened.

Overall, researchers estimate that about one in four California adults reported using cannabis in the past year, while about one in six reported using it in the past month across the entire study period.

The arrival of retail stores has therefore not led to a lasting increase in the number of consumers.

Why Legalization Has Not Led to a Sustained Increase

The authors assert that the’History of California helps explain these results. Long before recreational use was legalized, the state already had an extensive medical cannabis system in place, established following the adoption of the Proposition 215 in 1996. At the same time, a highly developed illicit market had long provided widespread access to cannabis-based products.

Since cannabis is already readily available before 2018, the expansion of legal access to retail sales may simply have changed purchasing habits rather than attracting a large number of new consumers.

The researchers also explain that the growing availability of psychoactive products derived from hemp outside the regulated cannabis market may have influenced consumption patterns in ways that were not accounted for in the survey.

Consumers are not using cannabis more often

The study also sought to determine whether existing users had begun using cannabis more frequently following the legalization of retail sales. Again, few changes were observed.

Among those who reported using cannabis in the past month, use remained concentrated at both ends of the spectrum throughout the study period. About 40% reported using cannabis between one and five days a month, while about 37% used it at least 20 days a month.

Intermediate consumption patterns remained much less common, and the overall distribution remained stable between 2019 and 2024.

These findings suggest that, although California’s regulated market has matured, this development has not been accompanied by an increase in consumption among people who already use cannabis.

Edible products continue to replace smoked cannabis

It is in terms of consumption patterns that the study highlighted significant and interesting changes for countries that still remain behind the wall of prohibition. Smoking remains the most common method of cannabis use, but its dominance has weakened considerably.

The proportion of consumers reporting that they use joints, pipes, or bongs fell from over 71% in 2019 to just over 58% in 2024. At the same time, edibles saw significant growth, rising from about 40% of consumers to more than 53% during the same period.

Other consumption patterns have seen relatively few changes. Vaping remained stable throughout the study, while « dabbing »showed a slight decline that did not reach statistical significance.".

The authors suggest that the increasing product diversity in the legal market in California, combined with increased awareness of health risks associated with combustion, could contribute to this gradual shift away from smoking.

Health clinics are now the main source of supplies

The legal market also appears to have become the primary source of cannabis for most users. Among users who had used cannabis in the past month and were surveyed between 2021 and 2024, approximately 77% reported obtaining cannabis from a dispensary.

Friends and family remained the second most common source, while delivery services accounted for a much smaller share. Home-grown produce and online purchases accounted for only a small portion of the reported supply.

Older adults are driving the biggest demographic shift

Although consumption at the state level remained largely unchanged, certain demographic groups showed different trends. The most significant increases were observed among middle-aged adults and the elderly.

Cannabis use in the past month has increased significantly among people aged 40 to 59, rising from 10.7% in 2017 to 14.5% in 2024.

An even more pronounced relative increase was observed among adults aged 75 and older, among whom the prevalence more than doubled during the study period, rising from 2.4 to 5.5 %.

On the other hand, the researchers found no significant increase among adults aged 18 to 25, despite widespread concerns that legalization could encourage increased use among young adults.

The study also revealed relatively stable trends by gender, while variations were modest across racial and ethnic groups.

A mature market rather than a rapidly growing one

Overall, these findings paint a picture of a California cannabis market that has continued to evolve without fundamentally altering the overall prevalence of adult use.

Rather than stimulating sustained growth in consumption, the legal market appears to have influenced the way consumers obtain and consume cannabis. Licensed dispensaries have become the primary retail channel, while the edible products continue to gain popularity at the expense of smoking products.

The authors point out that the study does not allow for the establishment of direct cause-and-effect relationships, as it is based on data from repeated cross-sectional surveys. They also note that changes in survey methodology, the COVID-19 pandemic and inconsistent local retail regulations in California may have influenced the results. More than half of California’s jurisdictions still prohibit commercial activities related to cannabis, which limits legal access in many parts of the state.

Nevertheless, this study offers one of the clearest long-term assessments of consumption trends since the start of retail sales to adults. Eight years after legal cannabis first hit store shelves, the data suggest that California’s legal cannabis market has become more sophisticated and diversified, though it has not seen substantial growth in the number of adults choosing to use cannabis.