Browse more cannabis research, findings, methods, and limitations.
A 30-day daily diary study found that young adult vapers alternate between nicotine-only days (53%), cannabis co-vaping days (40%), and combustible tobacco-cannabis days (7%), driven by sadness and cravings.
Database analysis found cannabis users had significantly higher implant infection, reoperation, and readmission rates after arm fracture surgery, supporting the need for routine cannabis screening in trauma patients.
A birth-to-age-23 study across two cohorts found that earlier cannabis initiation leads to more substance use problems, primarily by increasing frequency of use, with childhood aggression and parental cannabis use as early warning signs.
Analysis of 113,512 youth suicides found cannabis laws were associated with increased suicide deaths specifically among Asian/Pacific Islander (up to 42% increase) and Hispanic youth, with no effects in other racial groups.
First standardized comparison of cannabis excise taxes across 12 states found ~13% average tax incidence across product types, with wide state-to-state variation.
California city-level analysis found cannabis store authorization increased ER visits, hospitalizations, and poison center calls — with spillover effects into neighboring cities.
Analysis of 40,277 adolescents in 10 legal-cannabis states found that higher prices modestly reduced teen cannabis use (elasticity -0.21 to -0.33), but cannabis taxes alone had no significant effect.
Ex vivo placental study shows CBD crosses to the fetal side and dilates placental blood vessels by 36%, while THC constricts them — revealing opposing cannabinoid effects during pregnancy.
A comprehensive review finds cannabis disrupts the placental endocannabinoid system, linking use to fetal growth restriction and preeclampsia, with emerging evidence of transgenerational effects through epigenetic changes.
South African data shows cannabis treatment demand among youth didn't rise immediately after 2018 decriminalization, but increased by 50% from 2021-2023, particularly among adolescents and males.
A California cohort study found each additional dispensary within 1 mile increased young adult cannabis use by 5-6%, with smoking and edible use most affected but daily use unchanged.
A comprehensive review finds mixed evidence for cannabis as a pain treatment, with effectiveness depending on the cannabinoid, delivery method, and type of pain — underscoring the need for more rigorous research.
The Cannabis Exposure Inventory demonstrates reliable measurement of THC milligrams per using day (ICC=0.77), providing the first validated tool to quantify cannabis consumption beyond simple frequency counts.
Analysis of 854,878 adults found recreational legalization nearly doubled cannabis-only use and increased tobacco-cannabis co-use by 44%, while reducing tobacco-only use by 13%.
Analysis of 859,600 adults found legalization brings new users — especially older adults, women, and college graduates — into cannabis use without increasing frequency among existing users.
Analysis of 69,109 cannabis users found that recreational legalization shifted consumption toward edibles by 35%, particularly among males and older adults, while smoking declined.
Lab study finds CBD is much more effective than CBDA against colorectal cancer cells, with a whole-plant cannabis extract outperforming purified compounds — supporting entourage effects in anti-cancer activity.
Oregon poison center data shows that THC edible doses >30 mg cause severe symptoms in 28% of children under 6, with most experiencing significant CNS depression.
Women with endometriosis using prescribed medicinal cannabis reported pain reduction from 5.5 to 3.8 and quality-of-life scores nearly halving over 12 weeks, though the study lacked a control group.
A study of 822 college students found that unmet psychological needs drive simultaneous alcohol-marijuana use through coping motives, especially when students expect positive effects from combining substances.
Rats developed clear THC tolerance after 7 days of dosing but showed no spontaneous withdrawal symptoms when THC was stopped — even with a sensitive behavioral measure.
Epilepsy monitoring unit data shows cannabis users have shorter stays and higher event capture rates, but significantly more depression, anxiety, and abuse histories than non-users.
First-ever study of cannabis use in dancers finds 15% report impaired dance performance, with coping-motivated use strongly linked to higher cannabis use disorder scores.
National survey data shows regular cannabis use nearly doubles the risk of eustachian tube dysfunction (ear pressure problems), independent of cigarette smoking, with combined substance use further increasing risk.
JAMA review found strong evidence for cannabinoids treating nausea, appetite loss, and seizures, but guidelines recommend against inhaled or high-potency cannabis for most conditions.
Analysis of 134 Delta-8 THC online stores found widespread health claims and social media marketing, with most noting lack of FDA regulation but 41% not even requiring age verification.
People with psychosis increased their cannabis use by nearly 10 percentage points after recreational legalization — larger than general population increases — with the effect linked to retail store openings.
Sexual minority men who used marijuana had 2-3x higher odds of disordered eating and muscle-enhancing behaviors including fasting, vomiting, diet pills, and steroid use.
A nationally representative survey estimates 7.2 million US adults have CHS symptoms, with 88.5% undiagnosed — revealing a massive gap between disease burden and recognition.
Two large cohorts (250,000+ participants) and genetic analyses find no link between cannabis use and cognitive decline or dementia risk in older adults.
A review found only 12 studies on cannabis for sickle cell disease pain, with generally positive but mixed evidence — highlighting a major research gap for a condition affecting millions worldwide.
Among 484 Black young adults, childhood adversity and discrimination independently increased substance use, while foreign-born individuals had 40% lower cannabis use than US-born peers.
An 18-year-old chronic cannabis user developed spontaneous pneumomediastinum from forceful CHS vomiting — only the fifth such case reported — highlighting an underrecognized complication.
Swiss longitudinal study finds sexual minority males show the steepest cannabis and polysubstance escalation from 17-24, while sexual minority females plateau early — revealing distinct intervention windows.
Meta-analysis of 7,515 patients found ~34% with cannabis-induced psychosis later developed schizophrenia spectrum disorder and ~11% developed bipolar disorder.
Well-powered rat study found oral CBD did not significantly reduce acute opioid withdrawal symptoms, with limited sex-specific effects in the protracted phase.
Survey of 250 rheumatic disease patients found 75% interested in cannabis trials, but prior recreational use was the strongest predictor — raising concerns about selection bias in cannabinoid research.
Mouse study shows THC reduces chemotherapy-induced weight loss and preserves intestinal length, but doesn't reduce inflammation — suggesting benefits come from appetite stimulation.
ABCD Study data shows higher cognitive ability at ages 9-10 predicts cannabis use by 13-14, but positive cannabis expectations explain 73% of the effect — a clear prevention target.
National survey of 2,441 veterans finds significant regional differences in cannabis use (11.6%) and use disorder (2.9%), with geographic hotspots requiring targeted VA healthcare responses.
National data from 27,482 adolescents shows synthetic cannabinoid users have 48% higher odds of sports concussion, supporting SC screening at sports physicals.
A Phase II trial found that a traditional Thai cannabis-based herbal formulation matched lorazepam for insomnia treatment over 4 weeks, with comparable safety and sleep quality improvements.
National survey of 102,802 college students found transgender and gender diverse students had 58% higher cannabis use odds and more substance-related problems than cisgender peers.
Global Burden of Disease analysis of 204 countries finds cannabis use disorder is now the world's most prevalent drug disorder at 271 per 100,000, with legal-cannabis countries showing higher rates across all substances.
ABCD Study analysis of 11,868 youth finds transgender and questioning pre-adolescents show 1.7-2.5x higher cannabis curiosity by age 14, identifying an early prevention window.
A cannabis extract (NTI164) significantly improved OCD, tics, and ADHD in 14 children with PANS, with multi-omics showing it modifies the epigenetic and immune dysregulation underlying the condition.
Study of 238 deployed military finds PTSD specifically drives cannabis use, while combat exposure and moral injury drive prescription drug misuse — distinct pathways requiring different interventions.
Study of 900,000+ college students found stricter state cannabis policies associated with less cannabis use and less co-use with alcohol, with the two policy domains operating independently.
Oregon data shows cannabis retail density drives use in a dose-response pattern (up to 59% increase), while reducing heavy alcohol use among adults aged 21-24 and 65+.
Analysis of 41,374 gastroparesis patients found cannabis users had 73% more ER visits and 44% more hospitalizations, challenging the perceived benefits of cannabis for this condition.