Podcast Summary: The Science of Cannabis—Does It Help or Hurt With Anxiety? Is It Addictive? What's the Safest Way To Use It? | Dr. Riley Kirk
10% Happier with Dan Harris
Date: December 8, 2025
Guest: Dr. Riley Kirk, Ph.D. in pharmaceutical sciences, author of Reefer Wellness
Overview
In this episode, Dan Harris sits down with Dr. Riley Kirk—"radical scientist," researcher, educator, and cannabis user—to explore the nuanced science behind cannabis. The conversation delves deeply into cannabis’s benefits, risks, history, addiction potential, and its complex relationship with anxiety, offering an accessible yet thorough primer for anyone interested in using, understanding, or demystifying this plant.
Dr. Riley Kirk’s Background and Entry Into Cannabis
- Origin Story: Dr. Kirk started consuming cannabis at age 14 and noticed her seizures subsided after regular use. This personal experience sparked her deep dive into the science and stigma of cannabis.
- Professional Path: She studied natural products in pharmaceutical sciences, focusing later on cannabis for its remarkable medicinal potential and complexity.
- Advocacy: Kirk emphasizes shifting the conversation from “stoner culture” to a scientific, medicinal, and individualized approach.
"I wanted to be an advocate for the plant and start to discuss the science in a more professional setting so people can take it a little more seriously." (05:53)
Defining and Disentangling Cannabis Terms (12:19)
Key Glossary
THC: The psychoactive compound that gets you high.
CBD: Non-intoxicating, medicinally potent, especially for anxiety, inflammation, and seizures.
Hemp: The CBD-dominant “version” of cannabis; doesn't get you high.
Indica/Sativa: Originally botanical distinctions (Indica = sedating, Sativa = energizing), but most modern cannabis is a hybrid; these terms are now shorthand for effect profiles rather than strict plant types.
"All cannabis is Cannabis Sativa...what we call Indica and Sativa is now more about effect than plant lineage." (20:36)
CBD Hype vs. Reality (15:20)
- Many commercial CBD products are under-dosed; clinical effect requires 200mg or more.
"No research supports that five milligrams of CBD does almost anything for you." (16:12)
Individual Reactions, Dosing, and Personalization (08:16, 23:47)
- Dose Matters: Low THC can help with anxiety; high doses often provoke anxiety and panic, especially in sensitive individuals.
"THC can work in what we call a biphasic manner—at low doses it can absolutely help with anxiety...but if you're using too much, it can absolutely cause anxiety and give people panic attacks." (08:36)
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Balancing with CBD: Those sensitive to THC should use CBD-rich strains or mixed products, which can buffer against THC's anxious effects.
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Personalization: Product, dose, strain, and delivery method should be tailored for each user based on their goals and biochemistry.
"Cannabis is 400 things...every strain you may try has a different ratio. My brain chemistry is different than your brain chemistry, so we're going to react really differently." (23:47)
Addiction, Dependency, and Daily Use (26:06)
- Addiction vs. Dependency: Cannabis activates dependency for some but does not ignite classical addiction pathways like opioids or nicotine.
- Comparative Framing: There’s stigma about daily cannabis users, but daily dependence on pharmaceuticals (SSRIs, caffeine) is commonplace.
"As long as cannabis isn’t causing harm...it’s okay to lean on the plant a little bit. It has helped so many people." (26:42)
- Red Flags: Inability to function without cannabis or using it as escapism may signal an unhealthy relationship.
"If you can’t socialize, leave your house, eat, or do anything without cannabis, you’re probably leaning on it a little too hard." (27:42)
Cannabis in Cultural and Scientific History (31:20)
- Early Use: Initially used for seeds and oil, with low THC content in traditional medicine.
- Smoking Origins: Discovery that burning the plant created new effects led to its recreational use.
- Racism and Prohibition: American anti-cannabis propaganda, criminalization, and the term "marijuana" were rooted in xenophobia and efforts to marginalize Black and Mexican American communities.
"We made cannabis a Schedule 1 drug because they were typically the ones that were...smoking the cannabis." (37:40)
On ongoing injustice: "People are still in prison for cannabis, as we have this multi-billion dollar industry...It’s bananas to think about." (40:20)
- Scientific Discovery: Israeli researchers discovered THC and the endocannabinoid system in the late 20th century.
The Endocannabinoid System (ECS): How Cannabis Works in the Body (45:15)
- ECS Role: Body’s internal system producing cannabinoids, regulating sleep, appetite, mood, and pain, aiming for homeostasis/balance.
- Cannabis Mimicry: Plant cannabinoids tap into this system to produce effects.
"All animals...have an endocannabinoid system. Its purpose is to maintain balance in the body." (45:23)
Evidence-Based Benefits—and Where the Science Is Strong (48:35)
Areas with Strongest Research:
- Chronic Pain: THC helps reduce persistent pain signals.
- Seizures: CBD is well-evidenced for rare/severe types; the pharmaceutical Epidiolex is just CBD.
- Appetite Stimulation: Vital for cancer and HIV/AIDS patients who need to eat more.
- Sleep: Can help people fall and stay asleep, but might reduce REM sleep, affecting dream quality.
"Chronic pain, seizures, appetite—these are backed by the strongest data. For cancer, it’s a mixed picture depending on type." (48:35)
- Menopause: ECS regulation can help women with mood, sleep, and hormonal changes; low starting doses are recommended. (53:18)
Less Conclusive But Promising/Popular Areas
- Creativity & Productivity: Most evidence is anecdotal or survey-based. Cannabis may help by reducing distractions rather than directly “creating” creativity.
"It kind of turns off these other things in our brain that might inhibit us from being creative." (54:30)
Risks, Pitfalls, and Special Populations
Anxiety and Psychosis (60:06)
- Anxiety: Most common adverse effect, especially in naïve or sensitive users, and with high-THC modern products.
- Schizophrenia: Cannabis doesn't cause schizophrenia but may lower the age of onset in the genetically predisposed.
"THC does not cause schizophrenia, but it can decrease the age in which you experience your first episode." (62:39)
Lung Health
- Smoking: Less carcinogenic than tobacco but still introduces tar—long-term heavy use can damage lungs.
- Vaping: Healthier if using dry herb vaporizers; beware of synthetic, lower-quality vape oils which may contain heavy metals.
"For me, I always stick to cannabis flower...using a vape like this, you can actually still vape but use flower." (64:08)
Edibles and Tinctures (66:10)
- Up to 20% of people can't process edibles due to genetic enzyme differences.
- Edibles produce a heavier “body high”; inhalation is more “cerebral.”
Adolescents and the Developing Brain (67:50)
- Risks include possible changes to brain structure; modern high-THC vape products pose unknown, potentially higher risks than past use.
- Advice: Harm reduction—“wait as long as you can,” use low doses, titrate carefully.
Harm Reduction, Dosing, and Best Practices (75:14)
- Dosing: Start low, go slow. It’s always possible to take more, never to "untake."
- Sourcing: Legal dispensaries (ensure products are tested and labeled) or grow your own for purity, quality, and customization.
"I'm a huge proponent for homegrown cannabis—it's usually lower test, more balanced, and you know exactly where it came from." (75:35)
Special Considerations
Driving Safety (71:43)
- Unsafe for inexperienced users; experienced users with tolerance showed little increased risk in studies but self-monitoring is crucial.
"For naive users, it is not safe to drive...for medical consumers, the risk is much less." (71:47)
Pets (73:35)
- THC is dangerous for dogs (especially), as their endocannabinoid receptors are more concentrated in areas controlling movement and digestion.
- CBD is safe for pets; THC should not be administered.
"Don't dose your animals—it's not safe for them...they can get really uncomfortable and feel poisoned." (73:50)
Notable Quotes
- "THC can work in what we call a biphasic manner—at low doses it can help with anxiety...but too much almost always makes it worse." (08:36, Dr. Kirk)
- "We made cannabis a Schedule 1 drug...not based on science, but to prohibit Mexicans and African Americans from using the plant." (37:40, Dr. Kirk)
- "For me, cannabis is always my medicine...I've never been on a pharmaceutical medicine." (22:58, Dr. Kirk)
- "Cannabis can be extremely safe and effective medicine…I would highly recommend people explore it. But if you continually have negative experiences with cannabis, it’s okay to stay away from it as well." (80:32, Dr. Kirk)
Practical Takeaways
- Cannabis is complex: The plant, like people, varies tremendously; responsible use is highly individual and requires some experimentation and education.
- Health Benefits: Chronic pain, epilepsy, appetite stimulation, and sleep—where research is strongest.
- Risks: Anxiety, dependency for some, psychosis risk only in predisposed, and greater risks for adolescents.
- Delivery Matters: Smoking, vaping (preferably with flower), edibles, tinctures—all produce different effects and health implications.
- Sourcing: Buy from legal, regulated sources or grow your own; avoid unregulated oils and products, especially from gas stations.
- Start low and go slow: Especially when using new products, changing strains, or starting out.
Where to Learn More
- Dr. Riley Kirk’s book: Reefer Wellness: Understanding Cannabis Science, Culture and Medicine
- Podcast: Bioactive
- Social: TikTok, Instagram, YouTube (@cannabichem)
- Research Nonprofit: NAP (Natural Apothecary Project)
Memorable Moments & Timestamps
- Dr. Kirk’s first experience & stopping seizures: 04:59–06:36
- CBD hype vs. evidence: 15:20–16:45
- THC, anxiety, and dose response: 08:16–11:15
- Full history of cannabis, racism, and Schedule 1 status: 34:43–42:44
- Explaining the Endocannabinoid System: 45:15–47:48
- Risks of schizophrenia/psychosis: 60:06–62:39
- Risks for adolescents and modern products: 67:50–70:22
Closing Thought
Dr. Kirk concludes:
"If you continually have negative experiences with cannabis, it’s okay to stay away from it…Not every single person is going to react well to cannabis—that doesn’t mean we should limit access to this plant." (80:32)
Dan Harris wraps up by emphasizing the highly individualized, science- and harm-reduction-based approach to cannabis use advocated by Dr. Kirk—leaving listeners with both practical insights and a strong invitation to self-educate and experiment responsibly if they choose to partake.