Stress relief is among the most common reasons people give for using cannabis, and it is among the most common themes in how cannabis products are marketed. The scientific evidence supporting that pairing is considerably thinner than the marketing implies, and a new study from Oregon State University adds a complication rather than a confirmation.
Researchers found that frequent cannabis users woke up with higher levels of circulating cortisol, the body's primary stress hormone, than people who used cannabis rarely or not at all. The paper, "Subjective Stress and Diurnal Salivary Cortisol in Adults with Frequent Cannabis Use," was published in the journal Cannabis, with the university announcing the findings in July.
The study cannot establish direction. Stressed people may use more cannabis, frequent use may alter stress physiology, or both may be true at once.
The Measurement and What It Showed
The team, led by Anita Cservenka of the OSU College of Liberal Arts with colleagues Julia Donner and Alexia Obrochta, focused on the cortisol awakening response, or CAR. That is the normal rise in cortisol everyone experiences after waking, peaking around 30 minutes later, and it is treated as a marker of the body's readiness to meet the day's demands.
Calculating it is simple. Measure cortisol immediately on waking, measure again 30 minutes later, and subtract the first from the second.
According to the university's announcement, the CAR magnitude was similar in both groups. The difference was the starting point. Frequent users began the day with more cortisol already circulating.
The study is one of the few to examine frequent cannabis use in relation to the hypothalamic-pituitary-adrenal axis, the neuroendocrine system that governs the body's stress response.
"Our research suggests cortisol levels upon awakening may serve as a neurobiological marker of problematic cannabis use, and that connection needs to be investigated further," Cservenka said. She also noted that earlier studies had found a blunted CAR in frequent users, a finding this team did not replicate, which she attributed to "a lot of nuance that could be related to analytic strategies and sample characteristics."
One clarification for readers: some coverage, including the university's own release, has rendered CAR as "cannabis awakening response." It is the cortisol awakening response, a standard measure used across stress research regardless of cannabis.
The Larger Evidence Picture for Mental Health Claims
The cortisol finding sits inside a broader literature that has grown less supportive of cannabis for psychological symptoms, not more.
A systematic review and meta-analysis published in The Lancet Psychiatry in March, led by Jack Wilson at the University of Sydney's Matilda Center, screened thousands of studies and pooled 54 randomized controlled trials covering 2,477 participants published between 1980 and 2025. It is the largest randomized-trial-only analysis of cannabinoids for mental health and substance use disorders conducted to date.
As the university summarized, the review found no evidence that medicinal cannabis effectively treats anxiety, depression or PTSD, the three conditions driving most prescribing. It found no significant benefit for psychotic disorders, obsessive-compulsive disorder, anorexia nervosa or opioid use disorder, and it found that cannabinoids increased cocaine craving relative to placebo. Only four trials addressed sleep disorders. The authors concluded that routine use of cannabinoids for mental disorders and substance use disorders is currently rarely justified, while calling for more high-quality research rather than declaring the question closed.
One limitation of that review cuts in an unexpected direction, as ScienceDaily noted: most included trials used pharmaceutical-grade cannabinoid products rather than the high-THC products that dominate real-world markets. The trials tested a narrower pharmacological window than most consumers actually encounter.
Stress and anxiety are also not identical, and the absence of trial evidence for treating an anxiety disorder is not the same as evidence that cannabis provides no short-term subjective relief. Many users report exactly that. The unresolved question is what repeated use does to the stress-response system over months and years.
MedicalDaily Evidence Check
The Oregon State study is small and cross-sectional. It compared groups at a single point rather than following anyone over time, which means it captures an association and nothing more. Cservenka said so directly, telling reporters the work does not prove that frequent cannabis use causes higher waking cortisol or the reverse, and that the same people would need to be studied over a longer period to establish cause and effect.
Saliva cortisol is a validated but noisy measure influenced by sleep timing, waking time, caffeine, smoking, oral contraceptives and adherence to the sampling schedule.
The study also did not measure product potency, cannabinoid composition or route of administration, all of which vary enormously across the modern market and are likely to matter. A high-THC concentrate and a low-dose edible are different exposures.
What the finding contributes is a plausible biological reason to question the assumption that regular use resolves stress. What it does not do is establish that cannabis raises cortisol, that elevated waking cortisol in these participants caused any health outcome, or that anyone should change their use based on this paper alone.
The context that makes it matter is scale. The researchers note that 29 percent of U.S. adults aged 19 to 30 report cannabis use in the previous 30 days, a figure that has nearly doubled over the past decade.
The Regulatory Gap Around the Claims
Marketing has outpaced the evidence partly because of where cannabis sits in federal law.
Because cannabis remains federally controlled, the FDA does not permit therapeutic claims for cannabis products, and the FTC requires that any health claim be substantiated by scientific evidence. Both agencies have sent warning letters to companies advertising stress relief, sleep improvement and pain management without adequate support.
The practical result is a vocabulary workaround. Products are described as promoting calm, recovery, mental clarity or balance, and dispensaries organize inventory around symptom categories without stating a treatment claim outright. The only cannabis-derived prescription medicine with full FDA approval in the United States is a purified cannabidiol formulation for certain rare seizure disorders, an indication with no bearing on stress.
For consumers, the useful filter is simple. A product label or budtender recommendation is not clinical evidence, and effects vary by product, dose, cannabinoid ratio and individual. Anyone using cannabis for persistent stress, anxiety, low mood or sleep problems should tell a clinician, because those symptoms have treatments with far stronger evidence behind them, and because cannabis interacts with several common medications. Anyone with a personal or family history of psychosis or bipolar disorder should discuss use with a doctor before continuing.
Frequently Asked Questions
What did the new study find? Frequent cannabis users woke with higher circulating cortisol than infrequent or non-users, though the size of the morning cortisol rise was similar in both groups.
Does it prove cannabis raises stress hormones? No. It is a small cross-sectional study, and the lead researcher said explicitly that direction and causality remain undetermined.
What does the broader research say about cannabis and mental health? A March 2026 Lancet Psychiatry meta-analysis of 54 randomized trials found no evidence of benefit for anxiety, depression or PTSD, no significant benefit for several other disorders, and increased cocaine craving relative to placebo.
Is there any cannabis-derived medicine with FDA approval? Yes. A purified cannabidiol formulation is approved for certain rare seizure disorders. That indication has nothing to do with stress or anxiety.
Why do so many products advertise stress relief? Federal law bars therapeutic claims, so marketing uses wellness vocabulary such as calm, balance, and recovery. Regulators have sent warning letters over unsubstantiated claims.
Who should be most cautious? Anyone with a personal or family history of psychosis or bipolar disorder, and anyone taking medications that interact with cannabis.
What should someone using cannabis for stress do? Tell a clinician. Persistent stress, anxiety, low mood and sleep problems have treatments with substantially stronger evidence behind them.
