A changing cannabis landscape
Since California approved medical cannabis in 1996, cannabis products have become more widely available in the United States. Today, offerings range from traditional products to THC-infused drinks and edibles. Their growing presence has renewed questions about how use affects health--and what evidence is still missing.
One major shift is product potency. Some concentrated cannabis products contain far more THC than the lower-potency cannabis common in earlier decades. As products diversify, accurately communicating their ingredients and dosage becomes increasingly important.
Research highlights questions for public health
A University of Michigan study found that teenagers who vaped cannabis were twice as likely to report respiratory symptoms, such as wheezing, as teens who vaped nicotine or smoked cigarettes. The finding adds to ongoing research into how different ways of using cannabis may affect the body.
National data published in 2025 indicate that 15 percent of surveyed U.S. adults reported daily or near-daily cannabis use. Among daily users, 18 percent reported symptoms consistent with cannabinoid hyperemesis syndrome, which can involve recurring nausea and vomiting. These figures point to a need for clearer understanding, diagnosis and communication about frequent use.
At the same time, cannabis can have a role in some medical settings, including care involving chronic pain. The overall health effects are not uniform, and evidence about long-term outcomes and newer products remains incomplete.
More evidence, clearer information
Three decades of legalization have brought broader access, new product formats and a growing body of research. The next step is to improve product standards and public information while continuing to study both potential benefits and risks. Better evidence can help shape a future in which decisions about cannabis are more informed and health guidance keeps pace with changing products.
