Cannabis and Your Heart: What THC vs CBD Do Differently
What Researchers Found About and Cannabis
The Study at a Glance
Published
Journal of the American Heart Association, 2024
Researchers
University of Guelph (United States)
Study Type
Randomized Controlled TrialParticipants
22 patients · Acute study
Key Finding
THC significantly increases heart rate (~17 bpm), arterial stiffness, and reduces cardiac function—effects that could increase cardiovascular risk. CBD did NOT cause these cardiovascular effects. Smoking vs vaping THC made no difference.
Key Finding: THC significantly increases heart rate (~17 bpm), arterial stiffness, and reduces cardiac function—effects that could increase cardiovascular risk. CBD did NOT cause these cardiovascular effects. Smoking vs vaping THC made no difference.
What Researchers Studied About This Condition and Cannabis
What does cannabis actually do to your heart? This critical question becomes more important as cannabis use increases.
This 2024 trial from the Journal of the American Heart Association directly measured how THC and CBD affect cardiovascular function—comparing heart rate, arterial stiffness, and cardiac function.
This is one of the first studies to directly compare THC vs CBD cardiovascular effects in a controlled setting.
How This Randomized Controlled Trial Was Conducted
Researchers conducted a randomized controlled crossover trial:
• 22 young, healthy cannabis users • Each participant tested under 3 conditions (different days) • Condition 1: Smoked THC-dominant cannabis (S-THC) • Condition 2: Vaporized THC-dominant cannabis (V-THC) • Condition 3: Vaporized CBD-dominant cannabis (V-CBD) • Measured before and after: heart rate, arterial stiffness (pulse wave velocity), vascular function, cardiac function via echocardiography
This Condition Treatment Results
The Main Results:
- 1THC increased heart rate by ~17 beats per minute (both smoking and vaping)
- 2CBD did NOT significantly increase heart rate
- 3THC increased arterial stiffness (pulse wave velocity)
- 4THC reduced diastolic cardiac function
- 5CBD did NOT cause these cardiovascular impairments
- 6Smoking vs vaping THC made NO difference in cardiovascular effects
By the Numbers
| Statistic | What It Means |
|---|---|
| +17 bpm | heart rate increase with THC |
| No change | heart rate with CBD |
| Increased | arterial stiffness with THC |
| 22 | healthy participants tested |
heart rate increase with THC
heart rate with CBD
arterial stiffness with THC
healthy participants tested
What This Means for This Condition Patients
This study has important implications for cardiovascular safety:
THC affects your heart: • Increases heart rate by about 17 beats per minute • Stiffens your arteries • Reduces cardiac function (how well heart relaxes) • These effects could increase cardiovascular risk over time
CBD appears cardiovascularly safer: • CBD did NOT significantly affect heart rate • Did not cause arterial stiffening • Did not impair cardiac function
Smoking vs vaping - no difference: • Both methods produced the same cardiovascular effects • Don't assume vaping is safer for your heart than smoking (for THC)
Who should be cautious: • People with heart disease or high blood pressure • Those at cardiovascular risk • Older adults • Anyone concerned about heart health
Practical takeaway: If cardiovascular effects concern you, CBD products may be a safer choice than THC products.
Quick Answers: This Condition and Cannabis
Direct answers based on the findings of this study:
Research Summary: Answers are based on published peer-reviewed studies and represent research findings, not medical recommendations. Individual results may vary. Always consult a healthcare provider before making treatment decisions.
Is weed bad for your heart?
THC raises heart rate by about 17 beats per minute, stiffens arteries, and reduces heart function according to a 2024 American Heart Association study. If you have heart problems, this is important to discuss with your doctor.
Source: Al-Rifai et al., Journal of the American Heart Association, 2024 (PMID: 39575727)
Does smoking weed increase heart rate?
Yes, significantly. THC increases heart rate by about 17 bpm whether smoked or vaped. It also stiffens arteries and reduces cardiac function. These effects could be risky for people with heart conditions.
Source: Al-Rifai et al., Journal of the American Heart Association, 2024 (PMID: 39575727)
Is vaping weed better for your heart than smoking?
No—a 2024 study found identical cardiovascular effects from both methods: increased heart rate, stiffer arteries, reduced heart function. Don't assume vaping is safer for your heart.
Source: Al-Rifai et al., Journal of the American Heart Association, 2024 (PMID: 39575727)
This is educational content, not medical advice
The research summarized here is for informational purposes only. Individual results may vary, and what works in studies may not work the same way for everyone. Always consult with a qualified healthcare provider before making changes to your treatment plan or starting medical cannabis therapy.
Important Limitations
This study has some caveats to keep in mind when interpreting the results:
- Small sample size (22 participants)
- Young, healthy participants—effects may differ in older/unhealthy
- Acute effects only—long-term implications uncertain
- Single dose per condition
- May not apply to all cannabis products
The Bottom Line on Cannabis for This Condition
This American Heart Association study provides clear evidence that THC—whether smoked or vaped—significantly affects cardiovascular function: increasing heart rate by ~17 bpm, stiffening arteries, and reducing cardiac function. CBD did NOT cause these effects. For patients with cardiovascular concerns, this data suggests CBD-dominant products may be cardiovascularly safer than THC-dominant ones.
Do You Qualify for Medical Marijuana?
If you're living with qualifying condition, you may qualify for a medical marijuana card. Our licensed physicians can evaluate you from home via telehealth.
Related Research & Resources
Related Research
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This condition qualifies for medical marijuana in:
Source
Cheung CP, Coates AM, Baker RE, Burr JF "Acute Effects of Cannabis Inhalation on Arterial Stiffness, Vascular Endothelial Function, and Cardiac Function" Journal of the American Heart Association. 2024. DOI: 10.1161/JAHA.124.037731
Important Information
Not Medical Advice: This research summary is for educational purposes only. It should not be used to diagnose, treat, cure, or prevent any disease or medical condition. Always consult a qualified healthcare provider before starting or changing any treatment.
Individual Variation: Research findings represent group averages. Your individual response to cannabis may differ based on genetics, other medications, underlying conditions, and many other factors.
Last reviewed: January 24, 2026
Important Notices
Research Summary Disclaimer
This content represents our interpretation of published scientific research for educational purposes. It should not be used to make treatment decisions without consulting a qualified healthcare provider. Individual results may vary from study findings.
FDA Notice
These statements have not been evaluated by the FDA. Cannabis is not intended to diagnose, treat, cure, or prevent any disease. The FDA has not approved cannabis for any medical condition except specific prescription medications.
Copyright & Fair Use
Research summaries are provided under fair use (17 U.S.C. § 107) for educational purposes. We provide brief summaries with attribution, not full reproductions. All studies remain the intellectual property of their respective authors and publishers.
Data Sources
Study information sourced from PubMed®, U.S. National Library of Medicine. Inclusion does not imply endorsement by NLM, NIH, or the federal government.
For complete information, see our Terms of Use and Research Content Policy.
FAQs: Cannabis for This Condition
Does cannabis affect heart rate?
THC does—increasing heart rate by about 17 beats per minute. CBD does NOT significantly affect heart rate. This study found the same effects whether THC was smoked or vaporized.
Is CBD safer for the heart than THC?
Yes, THC affects the heart more than CBD. THC increased heart rate, stiffened arteries, and reduced cardiac function. CBD did not cause these cardiovascular effects in the same participants.
Is vaping cannabis safer for your heart than smoking?
No, according to this study. Both smoking and vaping THC produced the same cardiovascular effects—increased heart rate, arterial stiffness, and reduced cardiac function.