California Cannabis Use Survey Reveals Growing Consumption and Knowledge Gaps

Researchers at the University of California, San Diego, conducted an extensive survey involving over 5,000 residents to analyze cannabis consumption patterns following the legalization of recreational marijuana in California through Proposition 64 in 2016. The Initiative made it legal for adults aged 21 and older to use cannabis recreationally across the state. The survey, named Impact 64, provides valuable insights into how Californians are integrating cannabis into their lives, including usage frequency, sources, perceptions, and interactions with healthcare providers.

The findings show that approximately 37% of adults in California reported using cannabis within the past three months. Among these users, 58% consumed it daily, and 40% engaged in very frequent use—multiple times daily. The vast majority (77%) purchased cannabis products from dispensaries, with 94% viewing these outlets as licensed and regulated.

Interestingly, regardless of whether individuals identified their use as medicinal or recreational, many reported health benefits. About 82% observed emotional improvements, 81% noted mental health benefits, and 62% experienced physical health enhancements from cannabis use. Despite this widespread use, only two-thirds (66%) of users said their doctors are aware of their cannabis consumption, and just 15% sought medical guidance or information about it.

The study also highlights that most users (78%) felt comfortable discussing cannabis with their healthcare providers, yet gaps remain in both public and professional knowledge about cannabis laws, safety, and health impacts. The rapid growth of California's cannabis industry—exceeding $4.2 billion in sales in 2024—further underscores the importance of targeted education efforts to promote safe and informed use.

Supported by the California Department of Cannabis Control and collaborations with market research firm Quester, the survey merged qualitative and AI-driven quantitative methods, ensuring that the results accurately reflect California's diverse population, including native Spanish speakers. The study also examined knowledge about cannabis laws and driving behaviors, with results expected in future publications.

Expert insights from the study authors emphasize the urgent need for better education for both consumers and healthcare professionals. Dr. Linda Hill, the study’s lead, stated that understanding the patterns and risks of cannabis use is essential for developing effective public health strategies. Co-lead investigator Dr. Thomas Marcotte added that further research is necessary to evaluate the evolving landscape of legal cannabis and its implications for public safety.

Ultimately, the Impact 64 survey sheds light on the prevalent use of cannabis in California, the gaps in safety and legal knowledge, and the crucial need for ongoing education to ensure responsible consumption while maximizing health benefits.