"We need more data before we can say for sure that there are long-term positive effects – but the short-term effects were very clear: CBD was linked to reduced tension and anxiety, with minimal side effects."
Dr. L. Cinnamon Bidwell, Associate Professor of Psychology and Neuroscience at the University of Colorado Boulder
The silent epidemic of our time
Anxiety disorders are now among the most common mental health issues out there, and they've been on the rise for decades. In Germany, almost 8 percent of adults were diagnosed with an anxiety disorder in outpatient care in 2023, with the rate for women nearly twice as high as for men (2). Worldwide, about 25 percent of people experience an anxiety disorder at least once in their lives (3). Since the COVID-19 pandemic, anxiety symptoms have become even more common, especially among young women aged 18 to 29 (2).
Conventional meds like antidepressants often work well for treating acute anxiety and can effectively ease symptoms. But especially with long-term use, big problems can come up: side effects like trouble sleeping, sexual issues, and weight gain are common, and stopping the meds can cause strong withdrawal symptoms. There's also evidence that they can lose effectiveness over time, and there are health risks with long-term use.
With all these issues, it's no surprise that lots of people are looking for plant-based alternatives to conventional meds. Cannabidiol (CBD) has been in the spotlight for years now. But how strong is the evidence for CBD's effectiveness, really? New research is now giving us more solid data on how CBD-dominant cannabis products affect anxiety symptoms, with surprisingly positive results (1).
What makes this study published in Cannabis and Cannabinoid Research in February 2024 so remarkable:
It's the first randomized study to look at commercially available cannabis products in real-world use (1). The research team led by Dr. Cinnamon Bidwell recruited 300 participants with anxiety symptoms and split them into different groups.
The 258 cannabis users among them were quasi-randomly assigned to one of three product groups: a THC-dominant product (24% THC, 1% CBD), a CBD-dominant product (24% CBD, 1% THC), or a balanced product with 12% THC and 12% CBD. A control group of 42 non-users served as a comparison (1).
Because US federal law bans cannabis on university campuses, the researchers took a mobile lab to participants' homes. There, they tested them before and right after consumption, over a four-week period. During that time, participants could use the products however they wanted. On average, they used them about three times a week (1).
The research was funded by public NIH grants, and the authors clearly state they have no competing financial interests (1).
The results: CBD stands out with a clear profile
At the end of the study, all four groups reported reduced anxiety symptoms. But the cannabis groups showed much bigger improvements than the control group, and the CBD-dominant group did the best (1).
What's especially interesting is that people in the CBD group reported a noticeable reduction in tension right after using it, without feeling impaired. They also experienced significantly less paranoia than those in the other two cannabis groups (1). So the study backs up earlier findings that CBD might help reduce some of the negative acute effects of THC.
"Our results suggest that THC didn't increase anxiety in the long run, and that CBD-dominant cannabis was linked to a quick drop in tension, which might turn into longer-term anxiety reduction," sums up Gregory Giordano from the CU Center for Health and Neuroscience, Genes and Environment (CUChange) (1).
The scientific context: What we already know
The Colorado study isn't alone. A recent meta-analysis published in Psychiatry Research in September 2024 looked at eight randomized studies with a total of 316 participants. The result: CBD showed a significant effect on anxiety symptoms with a pretty impressive effect size (4).
Back in 2015, a groundbreaking review from the New York University School of Medicine pulled together preclinical and clinical evidence. Dr. Esther Blessing and her team concluded that preclinical findings suggest CBD looks promising for generalized anxiety disorder, panic disorder, social anxiety disorder, OCD, and PTSD, at least with acute use (5).
"There's good evidence that CBD could be an effective treatment for anxiety and other disorders," says Dr. Blessing. "But we need clinical trials to find out." (6)
A systematic review from 2024 that analyzed eleven randomized controlled trials backs up this cautiously optimistic view. Despite differences in dosages and study designs, the data suggest that CBD could reduce anxiety symptoms, with minimal side effects compared to placebo (7).
So, overall, the current studies basically support the results of the Colorado study. But most earlier human studies only looked at single, acute doses of CBD. The Colorado study is the first to add real-world use, commercially available products, and a longer observation period of four weeks to the mix.
The biological perspective: How CBD might work
From a pharmacological point of view, CBD is a remarkable molecule. Unlike THC, it has only a low affinity for the endogenous cannabinoid receptor 1 (CB1R), but acts as an indirect agonist. CBD also interacts with many other receptors in the body that aren't part of the endocannabinoid system (ECS), like the serotonin 5-HT1A receptor, which plays a key role in regulating anxiety and mood, as well as the TRPV1 receptor, which is involved in processing pain and emotions (5).
Dr. Bidwell suspects that the stronger anti-inflammatory properties of CBD compared to THC could also play a role: “It's possible that CBD-dominant products could reduce anxiety by inhibiting inflammation in the brain and nerves". Interestingly, even a low THC content of 1% could have a quick effect on mood (1).
Important limitations: What research doesn't show yet
Despite all these positive results, scientific caution is still needed. The current state of research has several limitations: Most human studies so far have only looked at acute, one-time doses of CBD. There’s still a lack of solid data on long-term use and optimal dosages (5). The Colorado study lasted four weeks, but that's still too short for solid statements about long-term effects.
The dosages in the different studies varied a lot, from low doses to several hundred milligrams per day. A clear dosing guideline can’t be drawn from the current literature yet (7).
Also, the Colorado study focused on cannabis flowers for inhalation. Whether the results can be transferred to other forms like oils or capsules is still unclear.
For context: Not a therapy recommendation
It's important to stress: These research results are not a medical treatment recommendation. If you’re dealing with anxiety disorders, you should reach out to qualified doctors or psychotherapists. Anxiety disorders are treatable, and there are evidence-based therapy options, from cognitive behavioral therapy to different classes of medication.
CBD products are available in Switzerland and the EU as dietary supplements, but as such, they’re not always subject to standardized quality control by all providers.
Looking ahead: A substance to be taken seriously
The Colorado study marks an important milestone in CBD research. For the first time, it was investigated under real-world conditions and with commercially available products how different cannabinoid profiles affect anxiety symptoms. The results are encouraging – but they're also a call for more research.
“Our study suggests that CBD products could relieve anxiety in the moment for adults who use them, and possibly in the long run too – in a way that's meaningful and doesn't necessarily carry the same risks or harms as THC or prescription meds", sums up Dr. Bidwell. “We need more data before we can give final recommendations, but this is promising news." (1)
Science is taking CBD seriously – and so should we. Not as a miracle cure, but as a substance with interesting therapeutic potential that deserves more research.
Note
This article is for informational purposes only and does not replace medical advice. If you have anxiety disorders or other mental health concerns, please contact a qualified professional.
