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How Cannabis Impacts Health & the Potential Risks | Dr. Matthew Hill

Episode 184 Jul 8, 2024 3h 52m 19 insights
In this episode, my guest is Dr. Matthew Hill, Ph.D., a professor of cell biology and anatomy at the Hotchkiss Brain Institute at the University of Calgary and an expert on the biology of cannabis. We discuss how cannabis affects the brain to produce its psychoactive effects (feeling “high”), including altered time perception, focus, memory, appetite, and stress. We discuss how THC vs. cannabidiol (CBD) affects the brain, the effects of different routes of cannabis administration (e.g., smoking, vaping, edibles), high-potency THC, and whether cannabis is addictive. We discuss if there is a link between cannabis use and the development of psychosis, anxiety, bipolar depression, or schizophrenia.  We discuss whether CBD has clinical benefits in regulating stress, promoting sleep, and treating certain diseases. We also discuss if there are real and consistent differences in the biological effects of different cannabis strains, if cannabis impacts hormones, and the uses of cannabis for the management of pain, stress, Post-traumatic stress disorder (PTSD), anxiety, and nausea. Listeners of this episode will get an up-to-date understanding of what is currently known about how cannabis affects the brain and body, including both its potential benefits and risks. Access the full show notes for this episode at hubermanlab.com.
Actionable Insights

1. Avoid Cannabis with Psychotic Risk

Individuals diagnosed with schizophrenia or bipolar disorder, or those with a first-degree family member having these conditions, should avoid cannabis to prevent triggering or accelerating disease onset and worsening long-term prognosis.

2. Avoid Cannabis with Cardiovascular Issues

Individuals with pre-existing cardiovascular issues should avoid cannabis due to potential risks like tachycardia and vascular effects, which could unmask vulnerabilities or trigger events.

3. Cease Cannabis for Fertility Issues

If struggling to conceive, both males and females should consider cutting out cannabis use, as it may negatively impact sperm quality or overall fertility in some individuals.

4. Avoid Cannabis During Pregnancy

Most people stop cannabis use upon learning of pregnancy; it is advisable to avoid cannabis during pregnancy due to unknown effects on the developing fetus and potential legal ramifications if accidental pediatric ingestion occurs.

5. Secure Edibles from Children

Store THC-containing edibles securely away from children, as accidental ingestion can lead to severe intoxication, emergency room visits, and potential legal consequences for parents.

6. Practice “Low and Slow” Edible Dosing

When consuming cannabis edibles, start with a very low dose (e.g., 2.5-5mg THC) and wait at least 90 minutes for effects to manifest before considering additional intake, as onset is slow and effects can be potent and long-lasting.

7. Exercise Caution with Concentrates

Be extremely cautious with cannabis concentrates (e.g., dabs, distillates) as they can reach 90-98% THC, are difficult to titrate, and can lead to blood THC levels double to triple that of high-potency flower, increasing risks of adverse effects and tolerance.

8. Do Not Increase During Paranoia

If experiencing anxiety or paranoia from cannabis, do not consume more, as this will likely exacerbate the negative experience.

9. Prioritize Unprocessed Whole Foods

Consume the majority of your diet from unprocessed or minimally processed sources to ensure adequate intake of vitamins, minerals, probiotics, and micronutrients, supporting physical and mental health and preventing overeating.

10. Prioritize Electrolyte Hydration

Consume adequate electrolytes (sodium, magnesium, potassium) to prevent diminished cognitive and physical performance, especially upon waking and during physical exercise or hot days when sweating.

11. Control Sleep Environment Temperature

To fall and stay deeply asleep, and to wake up refreshed, ensure your body temperature drops by 1-3 degrees and then increases by 1-3 degrees, which can be achieved by controlling your sleeping environment’s temperature.

12. Seek Expert Online Therapy

Engage in therapy with a licensed therapist to gain insights into emotional and relationship life, understand oneself better, and inspire positive action, ensuring good rapport, emotional support, and directed guidance.

13. Titrate Inhaled Cannabis Carefully

When inhaling cannabis, especially higher potency flower, take small amounts and allow a few minutes for effects to manifest to avoid overconsumption and adverse responses.

14. Consider Edibles for Lung Health

To mitigate risks of lung damage, emphysema, and other issues associated with combustion from smoking cannabis, consider oral routes of administration (edibles).

15. Vaporize Plant Matter to Reduce Harms

If consuming cannabis via inhalation, consider vaporizing plant matter using a device that heats it without combustion, as this avoids harmful combustion byproducts found in smoking.

16. Caution with Oil-Based Vaping

Be cautious with oil-based cannabis vaping products, as their long-term health effects and specific chemical compositions are not well-researched or regulated, potentially leading to unforeseen harms.

17. Avoid Exercise Before Drug Test

If facing a cannabis drug test, avoid intense exercise or weight loss efforts beforehand, as these can release stored THC from fat cells back into the bloodstream, potentially causing a positive test even after abstinence.

18. Skepticism for Low-Dose CBD

Be aware that most reported effects from low-dose CBD products (e.g., 10-20mg) are likely placebo effects, as efficacious clinical doses for conditions like pediatric epilepsy are typically 1500-2000mg, and oral CBD has very poor bioavailability (around 4%).

19. Hot Shower for Cyclic Vomiting

If experiencing cannabis-induced cyclic vomiting syndrome, a hot shower or capsaicin cream application may provide relief, suggesting an interaction with thermoregulation or autonomic balance.