frequent cannabis use is linked to higher levels of the stress hormone cortisol at wake-up, according to a new study that compared saliva samples from 39 frequent users and 43 non-users. Researchers found that while both groups showed the normal cortisol increase during the first 30 minutes after waking, frequent users began the day with higher absolute cortisol levels the moment they opened their eyes.
Cortisol helps regulate blood pressure, blood sugar and metabolism during stress. Short-term cortisol increases are normal and adaptive, but sustained elevation over days or years correlates with higher risk of anxiety, depression and cardiovascular disease. The new study measured cortisol via saliva collected at wake-up and at subsequent points during the first 30 minutes of the day, then compared levels and self-reported stress between groups.
Key findings – Sample sizes: 39 frequent cannabis users and 43 non-users. – Measurement: Saliva cortisol at wake-up and during the first 30 minutes after waking. – Result: Frequent users had higher cortisol at the initial wake-up measurement; the magnitude of the 30-minute rise (the cortisol awakening response) was similar in both groups.
The study appears in the journal Cannabis and lists Anita Cservenka, an associate professor of psychological science at Oregon State University, as lead author. Cservenka said cortisol on awakening could be a measurable neurobiological marker associated with problematic cannabis use and recommended further research to test that claim.
How researchers interpret the result The authors stress that the study is observational and does not establish cause and effect. Higher wake-up cortisol in frequent users may reflect long-term alterations in the hypothalamic-pituitary-adrenal (HPA) axis from repeated cannabis exposure, differences in sleep architecture, timing of last use before sleep, or other behavioral and medical factors. The study did not assign participants to use cannabis or control use, so it cannot determine whether cannabis caused the cortisol change.
The paper also notes that earlier work found a blunted cortisol awakening response in frequent cannabis users. The current team did not replicate that blunted-response finding, suggesting results can vary with sample characteristics, analytic choices and measurement timing.
Limitations and research gaps – Small sample: 82 participants total limits statistical power and subgroup analysis by age, sex, socioeconomic status or co-occurring conditions. – Cross-sectional design: Measurements were taken at one point in time, preventing assessment of whether cortisol differences preceded or followed changes in cannabis use. – Unknown use details: The report does not provide comprehensive, standardized data on THC concentrations, product types, dosing, or exact time since last use for every participant—factors that can affect physiology.
Researchers recommend larger longitudinal studies that track participants over months or years, record product potency and timing of use, and measure mental and cardiovascular outcomes alongside cortisol. They also suggest controlling for sleep quality and other medications that influence HPA axis activity.
Implications for clinicians and users Clinicians should note this preliminary association when evaluating patients who report frequent cannabis use and symptoms related to mood or cardiovascular risk. For researchers and public-health planners, the study highlights a measurable physiological difference that warrants replication in larger, more diverse samples and in prospective designs.
Practical takeaways – The study reports a measurable, cross-sectional association between frequent cannabis use and higher cortisol at wake-up in a small sample. – The finding does not prove causation; it identifies a physiological pattern that needs confirmation. – Future studies should measure frequency, THC potency, timing of last use, sleep patterns and long-term mental and physical health outcomes.
Summary In a controlled comparison of 39 frequent cannabis users and 43 non-users, researchers measured saliva cortisol at wake-up and during the first 30 minutes thereafter. Frequent users showed higher cortisol at initial wake-up, while both groups had similar increases over the first 30 minutes. The study signals a possible link between regular cannabis use and altered stress-hormone levels, but it does not establish cause and effect. Larger, longer, and more detailed studies are needed to determine whether frequent cannabis use changes HPA-axis regulation or whether other factors explain the difference.
