The Benefits of Using THC and CBD
As legalized cannabis becomes more ubiquitous—it is currently legal in 10 states and the District of Columbia—it is worth investigating data on the links between tetrahydrocannabinol (THC), cannabidiol (CBD), and your health. CBD and THC are the two most researched compounds in cannabis.
CBD is a non-psychoactive compound typically extracted from the hemp plant. It binds weakly to CB1 receptors in the human body’s endocannabinoid system and can even inhibit THC binding. 
THC is the primary psychoactive component of marijuana, which delivers a high through smoking, edibles, oils, capsules, and other means.
Both compounds are equally composed of carbon, hydrogen, and oxygen; the distinction in their effects on neurotransmitters stems from a minor difference in their atomic structures. 
The Benefits of CBD
The medical benefits of CBD have been of interest for some time, with a 1980 study finding ubiquitous tolerance, no toxicity or serious side effects, and significant improvements among a majority of participants with epilepsy.  Subsequent studies reached the same conclusions, with CBD improving symptoms and quality of life in both pediatric and adult patients with epilepsy. [3-8]
Research into CBD as a potential treatment for other conditions is underway and ongoing. A 2017 trial of CBD as a treatment for Dravet syndrome showed a significant reduction in the frequency of total seizures among those given CBD (P =.03) but also demonstrated more adverse events, such as diarrhea and vomiting.  Another study showed efficacy and tolerability associated with CBD in the treatment of Lennox-Gastaut syndrome. 
CBD has a broader therapeutic index than THC, which suggests that it may have a greater number of pharmacological applications. In general, it is both effective and safe in treating neurological disorders, such as seizures.  CBD-rich extracts typically have better safety profiles than purified CBD products. Further standardization in the cannabis industry will aid in discovering the underlying reasons for this, though it seems likely that other cannabis compounds interacting with CBD may be responsible. 
The World Health Organization has stated that CBD is “well tolerated with a good safety profile.”  It has also demonstrated efficacy in treating post-traumatic stress disorder, panic disorder, general anxiety disorder, obsessive-compulsive disorder, and social anxiety disorder.  Additionally, it has demonstrated efficacy in suppressing rheumatoid arthritis disease activity. 
The Risks Associated With CBD
CBD is generally safe and tolerable among nearly all people. Side effects are typically mild and quick to resolve and include the following: 
- Dry mouth
In rare cases, CBD may be associated with abnormalities in tests for liver function. Note that research on long-term effects of CBD is limited. 
The Benefits of THC
Unlike CBD, THC binds to CB1 receptors in the human brain.  This produces a high that can include a sense of euphoria—and it is this high that has historically caused cannabis to be classified as an illicit drug. However, THC has demonstrated numerous health benefits in studies investigating its therapeutic qualities for different conditions, including:
- Back pain
A recent study has collected data on the comparative effects of THC and CBD through a mobile software app.  The study researchers found that THC was significantly associated with symptom improvement across 27 symptoms measured by an 11-point scale, with an average symptom improvement of 3.5±2.6 among participants.  Interestingly, this study found little association between CBD use and symptom change.
Furthermore, THC has shown early evidence of efficacy in treating other conditions such as cancer. According to cancer.gov, cannabinoids may exhibit a protective effect against tumor growth.  This antitumor effect may be related to cannabinoids’ tendency to inhibit cell growth and cause cell death among tumor cells but not healthy counterparts.  This underscores the need for further research into THC’s therapeutic benefits in a host of other conditions.
The Risks Associated With THC
Moderation is important with THC. Due to its associated high, THC carries a risk for addiction. It impairs motor skills, cognitive functioning, and behavior in the short term. 
Adolescents, for whom cannabis is the second most popular intoxicant, are particularly vulnerable to THC’s side effects.  Neuroimaging and assessments have revealed an association between marijuana use and deficiencies in neurocognitive performance, brain function, and brain development on both microstructural and macrostructural scales in adolescents.  Further studies will help researchers confirm or reject a causal link with brain function and marijuana use.
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2. Healthline. CBD vs. THC: What’s the difference? https://www.healthline.com/health/cbd-vs-thc
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