Frequent cannabis users show elevated 'stress hormone' levels upon waking, study finds

Research from Oregon State University, published in the journal Cannabis, found that people who use cannabis frequently start their day with higher cortisol levels than those who don't use it. The study, led by Anita Cservenka of OSU's College of Liberal Arts along with colleagues Julia Donner and Alexia Obrochta, is among the few to examine how frequent cannabis use relates to the hypothalamic pituitary adrenal axis, the neuroendocrine system that coordinates the body's stress response.

Stress is commonly cited as a reason people use cannabis, yet it is also linked to problematic use patterns. While cannabis may offer temporary stress relief, researchers say frequent long-term use could interfere with the biological systems that regulate the stress response.

Context: rising use among young adults

Cannabis use has grown sharply among young Americans over the past 15 years. Twenty-nine percent of adults aged 19 to 30 report using cannabis in the past month, nearly double the rate from 15 years ago, and more than 10% of that age group report using it at least 20 times within 30 days — also more than double the earlier rate.

The researchers focused on the cortisol awakening response (CAR), the rise in cortisol that everyone experiences roughly 30 minutes after waking, calculated by comparing cortisol measured right after waking with a measurement taken 30 minutes later. The size of that rise was similar between frequent users and nonusers, but frequent users already had more cortisol in their system at the moment of waking.

Cservenka cautioned that the findings do not prove cause and effect in either direction, and that longer-term studies following the same people over time would be needed. The team also did not replicate earlier research suggesting a blunted CAR in frequent cannabis users, underscoring how complex and inconsistent findings in this area remain, potentially due to differences in study populations and analytical methods. Cservenka noted the results could point to a feedback cycle in which a poorly regulated stress system encourages further cannabis use. The research was funded by Oregon State University, the OSU Center for the Humanities, and the OSU College of Liberal Arts.