CBD vs THC: A Biological Perspective
Cannabinoids and Human Biology
Cannabinoids are unique chemical compounds that occur naturally in all varieties of the cannabis plant. More than 100 different cannabinoids have been isolated from cannabis, with at least 80 having potential medical significance, but the most popular are cannabidiol (CBD) and tetrahydrocannabinol (THC).
The human body has an endocannabinoid system that is linked to the central nervous system and the peripheral nervous system. Endocannabinoids are chemical compounds, similar in shape to cannabinoids, that exist naturally in the human body. These compounds interact with cannabinoid receptors, together they can influence other body systems through nervous system messengers called neurotransmitters.
The endocannabinoid system is involved in regulating many systems in the human body. Cannabinoids from cannabis can interact with the receptors of the endocannabinoid system. This means that these cannabis-derived compounds have a very wide therapeutic potential. Since each person’s body is wired a little differently, it also means that there is no one cannabinoid preparation that will be right for every person and every symptom.
Cannabinoid Receptors
There are two main types of cannabinoid receptor in the endocannabinoid system. Cannabinoid receptor 1 (CB-1) was the first endocannabinoid receptor to be discovered, followed by cannabinoid receptor 2 (CB-2). They are found largely in the brain and nervous system but are also present in organs and tissue. When the receptors are activated by cannabinoids or endocannabinoids the initial effects are produced primarily in the brain and in the immune system.
Cannabinoids resemble naturally occuring endocannabinoids that are present in the human body so they can impersonate them to create the same effects. When cannabinoids pair with receptors, a lot of the cells they impact are neurotransmitters. Neurotransmitters are like the messengers of the body. Their signals can be carried all over the body through the central and peripheral nervous systems to create broad effects on several body systems.
By mediating cell communication through cannabinoid receptors, CBD and THC can provide relief from several symptoms of common diseases and disorders. Most prominently, cannabinoids can provide relief from symptoms of pain, nausea, anxiety, and inflammation, which are heavily influenced by the nervous system and immune system where endocannabinoids provide regulation.
CBD vs THC in Cannabinoid Receptor Activation
The issue of CBD vs THC comes from the observation that different cannabinoids have differing affinities for the cannabinoid receptors. THC binds readily to CB-1 receptors in the brain, while other cannabinoids will bind to receptors in other parts of the body. THC’s activation of CB-1 in the brain is attributed to the psychoactive effects of cannabis. Despite this effect, THC does stimulate other reactions that have great medicinal value. Unlike THC, CBD does not bind well to CB-1, which is why CBD does not have psychoactive effects like THC.
THC and CBD both show activity influencing pain and sleep, mood and behavior, spasticity and nervous disorders, gastrointestinal disorders, and relief from diseases and disorders with symptoms affecting multiple body systems (cancer, MS, glaucoma, HIV/AIDS). The interaction between the CB-1 and CB-2 receptors with cannabinoids like CBD and THC can produce broad health benefits such as pain relief, anxiety relief, appetite stimulation, and mood improvement.
There are very few health issues that cannot find relief through either THC or CBD, or preparations that contain both. Products such as oils that contain a full spectrum of cannabinoids including THC and CBD are very effective because they can act on more receptors than single cannabinoids. For patients that do not want to feel psychoactive effects, products like oils, tinctures, and edibles that contain miniscule levels of THC can provide the benefits of medical marijuana without the “high.”
Medicinal Benefits of CBD vs THC
Cannabis preparations have numerous therapeutic effects as an antispastic, analgesic, antiemetic, neuroprotective, and anti-inflammatory. In addition the the physical effects, cannabinoid based medicines can be effective against certain psychiatric conditions.
Common Conditions Treated with CBD
Common Conditions Treated with THC
Seizures (900-1200 mg/kg*)
Inflammation (general)
Pain
Mental Disorders
Inflammatory Bowel Disease
Nausea
Migraines
Depression and Anxiety (300 mg*)
Pain
Muscle Spasticity
Glaucoma
Insomnia
Low Appetite
Nausea
Anxiety
*Dose levels reflect reported research levels used and are not a specific medical dose suggestion evaluated by a licensed physician
CBD vs THC: Difference in Cannabinoid Chemical Structures
Both CBD and THC influence the endocannabinoid system by impersonating natural endocannabinoids in the body. CBD and THC have different effects because they interact differently with cannabinoid receptors. The slight difference in the molecular shapes of CBD and THC make this possible.
The shape of a molecule allows it to bind to receptors, when they fit together well it is like a key in a lock. When the key turns the lock, the effects are released. For CBD and THC the difference in shape comes down to the different position of a single molecule in the chemical compound’s overall shape.
Cannabinoids Beyond THC and CBD
In addition to CBD and THC, cannabis contains several other cannabinoids such as cannabinol (CBN), cannabigerol (CBG), tetrahydrocannabivarin (THCV), cannabichromene (CBC), and over 100 others.
Tetrahydrocannabinol (THC)
Primary psychoactive cannabinoid that activates CB-1 and CB-2 receptors
Produces the stereotypical “high” associated with cannabis, but also has significant medicinal value
Cannabidiol (CBD)
Non-psychoactive cannabinoid that does not bind well to CB-1 or CB-2, and can block other cannabinoids from binding to CB-1
Produces effects indirectly by promoting the naturally present endocannabinoids in the body
Produced from same chemical precursor as THC
Counteracts the “high” felt from marijuana with high THC (recreational cannabis varieties) and has significant medicinal value
Strong antioxidant activity neutralized reactive oxygen species (ROS) in the body that contribute to inflammation
Used in modern and traditional medicine as an antiepileptic and anticonvulsant
Antitumor properties that promote cancer cell destruction
Cannabinol (CBN)
Produced when THC molecules degrade from exposure to light and air during storage
Not present in high concentrations in fresh cannabis plants
Mild psychoactive properties
Strong affinity for binding to CB-2 with less affinity for CB-1
Cannabigerol (CBG)
Non-psychoactive contributor to general effects of cannabis
Promotes death of cancer cells and inhibits tumors in mouse studies
Binds to CB-2 and can block other cannabinoids from binding to CB-1
Tetrahydrocannabivarin (THCV)
Lessens psychoactive effects of THC by blocking binding of THC to CB-1
Cannabichromene (CBC)
Non-psychoactive cannabinoid with evidence of antitumor activity in mouse studies of breast cancer
CBD vs THC in Cannabis Plants
CBD and THC production in the cannabis plant is controlled by codominant genes. Codominant genes are genes that do not suppress each other from being expressed. This means that all cannabis plants will produce both THC and CBD. Through selective breeding cannabis plant varieties have been attained that produce THC and CBD in different proportions. Hemp plants, for example, are a type of cannabis sativa that are an ideal source for non psychoactive CBD oil because the plants and their byproducts must have less than 0.3% THC content.
Historically cannabis plants have belonged to the single species Cannabis sativa L. Over the years, a strong case has been made for a 2 or 3 species model that captures the major divergences in cannabinoid content and physical appearance due to selective breeding. The 2 species model is very commonly accepted today and differentiates between Cannabis sativa and Cannabis indica. Cannabis ruderalis is the third major cannabis variety that is still debated as being a different species of the plant.
Hybrids of the major varieties of cannabis have become very popular with the rise of medical marijuana. Hybrids are specially bred to have specific medicinal effects and can contain a wide variety of THC and CBD levels depending on the parent plants. These designer strains can vary widely in appearance, flavor, cannabinoid content, and overall effect on the body.
Properties of Cannabis Varieties
Cannabis Variety
CBD vs THC
Features
Cannabis ruderalis
Lowest levels of THC
Fast growing plant that flowers based on age instead of light exposure
No recreational value, naturally lowest levels of THC
Can be used to make non-psychoactive preparations of CBD oil but is not often used due to legal restrictions
Grows in the wild but is also very useful in creating unique hybrids
Short and skinny plant appearance
Cannabis sativa
Low THC %
Two main subtypes are a drug type (marijuana) and hemp- a fiber rich type
Drug type provides a more energizing high
Hemp type can be used to make non-psychoactive CBD preparations
Drug type can be psychoactive or non-psychoactive depending on THC content
Tall and skinny plant appearance
Cannabis Indica
High THC %
Drug type variety (marijuana)
Provides a psychoactive high with deep body relaxation
Medicinal preparations will have psychoactive effects
Plant appearance is shorter than Sativa and much bushier
Cannabis Hybrids
Variable
Variable, some are more psychoactive than others, and some are not psychoactive at all
Hybrids are usually categorized as having a high CBD vs THC ratio, having a low CBD vs THC ratio, or as having near equal levels of both
The three major varieties of Cannabis sativa L.
Medicinal Preparations of CBD and THC
There is a massive variety of cannabis products available. While drug producers are creating pharmaceutical grade product for treating severe illnesses, small producers are creating a range of products to cater to the legal allowances of their particular states.
Currently, only one pharmaceutical product is federally approved for use and sale, but more clinical trials are underway. State regulated cannabis products may or may not be psychoactive, so buyers need to take care when selecting products from a dispensary. Dispensary staff can be very helpful in guiding buyers to the type of product they are looking for so consulting with them is highly advisable.
Another type of cannabis product is derived from hemp. As long as these products contain no more than 0.3% THC they can be sold and produced within the entire US. These CBD oils are extracted from the hemp plant which is a non psychoactive variety of Cannabis sativa. They are less potent than extracts from the drug type cannabis plant but can have great benefits as a supplement. Similar to other nutritional supplements like vitamins, the effects of taking hemp-based CBD oils build over time.
These products have no psychoactive concerns, but the minute levels of THC that won’t get users high is able to be stored in body fat. Over time this storage does have the potential to trigger positive drug test results, so users will want to be vigilant of that.
Activating and Extracting Cannabinoids
Cannabinoids are present in the cannabis plant in an inert state that would not activate effects in the human body. To change cannabinoids to a useful version, the molecules have to be heated to remove part of the chemical structure. This process is called decarboxylation.
Cannabis plant floral buds are the main source of cannabinoids, especially THC and CBD. The flowers are harvested, dried, and then they can be sold and used as a dried herb, or processed further. Some degree of decarboxylation occurs with drying flowers, but decarboxylation mainly occurs when the ground flower is smoked or vaporized.
To make oils and other extracted forms of cannabis, leaves and stems of the plant can be used in addition to flowers. Plant materials are decarboxylated by baking or boiling in a hot water bath at low temperatures for an extended period of time. There are a large variety of extraction methods that can be used to coax cannabinoids out of the plant.
The most common and traditional way to extract cannabis is by using alcohol. Butane and propane can be used to make extractions, but are less desirable because of the chemical traces that can be left behind. Carbon dioxide extraction uses gas and high pressure to remove compounds from plant tissue and is one of the best methods for creating a very pure extract without chemical remnants.
Cannabis as a Nutraceutical
Nutraceuticals are a class of supplements that encompass ingredients that have nutritional benefits and health benefits. It is a broad product category that consists of products like some dietary supplements, isolated nutrients, functional foods like prebiotics, and botanical product.
Nutraceuticals differ from dietary supplements in that they are able to help with nutrition as well as aid in prevention and treatment of diseases. Cannabis nutraceuticals like CBD oils from hemp and cannabis essential oils have several benefits to a person’s general health.
Health Concern
Corresponding Cannabinoid Nutraceutical Compound
Inflammation
CBD, THC, CBC, CBG, THCV
Neuroprotection
CBD, Plant Terpene Compounds
Antioxidant
CBD, THC, Cannabis Essential Oil (several plant compounds including terpenes)
Obesity
THCV, CBD
Are Cannabinoid Medicines Addictive?
Hemp-based CBD oils have not been observed to have significant addictive or dependent properties. Use of marijuana-based products containing only CBD or combinations of CBD and THC have also shown to be very safe with very low incidents of addictive or dependent behavior. Surprisingly, even recreationally smoked marijuana has very low levels of addiction and very few long lasting withdrawal symptoms. Withdrawal symptoms are more commonly experienced by heavy chronic users of psychoactive varieties of cannabis.
A physician should always be consulted when it comes to expert opinions on risk of addiction, side effects of use, and symptoms of withdrawal. Overall, research on cannabis use in general has reported that cannabis products are safe and effective, but those general claims do not have federal clinical trial data to certify the safety of products that fall under state licensure.
The top three side effects of cannabinoid use are commonly reported to be tiredness, dizziness, and dry mouth. Some users will build tolerance an experience fewer or less intense side effects with continuous use. Contraindications exist for cannabinoid use and allergies to cannabis do exist.
Is CBD Right for Me?
THC and CBD products are safe but have different effects than products containing only CBD and other non psychoactive cannabinoids. Some users will have better results from one vs the other and from CBD vs THC. It’s important to keep an open mind when trying cannabis products because there is an endless variety of preparation to try. Medical marijuana is very much a personalized medicine and it may take some trial and error to find what works best for particular symptoms.
Apart from medical marijuana, hemp-based CBD products like nutraceutical CBD oil also has great health benefits for people and pets. Dogs have similar brain receptors to humans, so many in the veterinary industry have found hemp-based CBD products to help pets with symptoms of inflammation, muscle spasticity, anxiety, and nausea.
Qualities
CBD
THC
Psychoactive “High”
–
+
Illegal
+*
+*
Side Effects
–
+
Drug Test Positive
+**
+
Pain Relief
+
+
Nausea Relief
+
+
Migraine Relief
+
+
Anxiety Reduction
+
+
Appetite Increase
–
+
Anti Inflammatory
+
+
Seizure Decrease
+
–
*Both CBD and THC are illegal federally, some states have laws that make them legal for medical or recreational purposes, or both.
**CBD isn’t always detected but hemp products may contain trace amounts of THC. If that THC shows up in high enough concentrations it can produce a positive drug test.
References
Atakan, Z. (2012). Cannabis, a complex plant: different compounds and different effects on individuals. Therapeutic advances in psychopharmacology, 2(6), 241-54.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3736954/
Grotenhermen, F., & Müller-Vahl, K. (2012). The therapeutic potential of cannabis and cannabinoids. Deutsches Arzteblatt international, 109(29-30), 495-501.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3442177/
Hartsel, J. A., Eades, J., Hickory, B., & Makriyannis, A. (2016). Cannabis sativa and Hemp. In Nutraceuticals (pp. 735-754). DOI: 10.1016/B978-0-12-802147-7.00053-X
Hillig, K. W., & Mahlberg, P. G. (2004). A chemotaxonomic analysis of cannabinoid variation in Cannabis (Cannabaceae). American Journal of Botany, 91(6), 966-975.
https://onlinelibrary.wiley.com/doi/pdf/10.3732/ajb.91.6.966
Roger G Pertwee. (2006). Cannabinoid pharmacology: the first 66 years. British journal of pharmacology, 147 Suppl 1(Suppl 1), S163-71.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1760722/