Scientists have isolated more than 113 chemical compounds in the cannabis sativa plant, more popularly known as cannabis. These naturally occurring compounds are called cannabinoids. The two most dominant and well researched cannabinoids in the cannabis genus are delta-9-tetrahydrocannabinol (THC) and cannabidiol (CBD).
Cannabinoids interact with our bodies through the CB1 and CB2 receptors found in the endocannabinoid system present in all mammalian species.
Raphael Mechoulam, organic chemist and professor of Medicinal Chemistry at the Hebrew University of Jerusalem, first isolated THC from cannabis in 1964. A year earlier he had elucidated CBD which was first discovered by Dr. Roger Adams of the University of Illinois in 1940. It was in 1965 when Mechoulam first synthesized THC and CBD. [R]
For decades, researchers have known that THC is the main psychoactive component of the cannabis plant – and responsible for making people high. THC works by mimicking the effects of anandamide and 2-AG which are neurotransmitters in the body that help modulate the perception of pain, sleeping and eating habits, and other bodily functions.
CBD, on the other hand, is non-psychotropic and therefore does not make people high. Cannabidiol is found in cannabis as well as agricultural hemp. While cannabinoids are present in many other flora species, cannabis is the only plant known to contain CBD.
CBD and THC have the same chemical formula but with the atoms arranged differently. This slight variance is what makes THC psychoactive and CBD non-psychoactive. Although both compounds interact with human cannabinoid receptors, they produce dramatically different effects.
The non-psychoactive nature of CBD makes it a popular ingredient in dietary and natural supplements. It does its work – symptom relief and medical potential – with little or no noticeable effect on your cognitive abilities. In fact, research has shown that CBD might be able to balance the psychotic effects of THC.
Origin and forms of CBD and THC
THC is found in marijuana. It is often consumed by smoking but is also available in oils, edibles, tinctures, capsules, and more.
CBD is found in marijuana and hemp. It is available in oils, tinctures, soft gels, gummies, and more.
Hemp vs. marijuana
Hemp and marijuana are both cannabis – hemp is cannabis sativa while marijuana is either cannabis sativa or cannabis indica. Hemp is the legal term for cannabis that contains less than 0.3% of THC. Marijuana is the legal term for cannabis that contains more than 0.3% of THC.
CBD is the same cannabinoid whether it is found in hemp or marijuana.
CBD vs. THC: chemical structure
CBD and THC share the same chemical formula – C21H30O2. They also share the exact same molecular structure: 21 carbon atoms, 30 hydrogen atoms, and 2 oxygen atoms.
The molecular mass of THC is 314.469 g/mol while the molecular mass of CBD is 314.464 g/mol. The biosynthesis of THC and CBD in cannabis also follows a nearly identical pathway. The only difference between the two cannabinoids is a slight variation in how the atoms are arranged.
Cannabis sativa does not produce THC or CBD. The precursor cannabigerolic acid (CBGA) is cyclized into tetrahydrocannabinolic acid (THCA) and cannabidiolic acid (CBDA) by synthase. Cannabis sativa extracts are non-psychoactive until sufficient heat is supplied to cause a chemical reaction known as decarboxylation. The final THC and CBD compounds are formed via decarboxylation of THCA and CBDA. [R]
Structurally, the two cannabinoids show one important difference: THC contains a cyclic ring while CBD contains a hydroxyl group. This seemingly small difference in molecular structure is what gives THC and CBD entirely different pharmacological properties and effects.
THC and CBD do not dissolve well in water but have good solubility in most organic solvents especially alcohol and lipids. Because of the ability of THC to bind to glass and plastic, THC preparations are typically stored in amber silicate glassware to preserve its integrity during analytical testing procedures.
CBD vs. THC: how they interact with the endocannabinoid system
CBD and THC are chemically similar to the endocannabinoids that are naturally produced by the human body. The interaction between cannabinoids and endocannabinoid receptors impacts the release of neurotransmitters in our brain. Neurotransmitters are responsible for cell signaling and communication.
The human endocannabinoid system has two types of cannabinoid receptors: CB1 and CB2.
CB1 receptors are found mainly in areas around the brain. They play an essential role in the perception of pain as well as regulating mood, memory, sleep, and appetite.
CB2 receptors are mostly located within areas of the immune system. CBD works as an anti-inflammatory agent when it binds to CB2 receptors.
Cannabinoid receptors are located throughout the body. This is why topical cannabis is able to work directly on skin, muscles, and any area with cannabinoid receptors.
Anandamide and arachidonoyl glycerol (2-AG) are the main endocannabinoids that our bodies produce. CBD, THC and the endocannabinoids found in our body can activate both CB1 and CB2 receptors.
THC mimics the effects of anandamide and 2-AG by also activating CB1 and CB2 receptors. CBD, however, does not seem to act directly on CB1 and CB2 receptors but rather helps boost the levels of endocannabinoids in the body.
When THC binds with CB1 receptors, it stimulates the body. The effects of this action include relaxation, altered senses, fatigue, and hunger. The munchies – or strong craving for food after smoking marijuana – are a direct side effect of THC.
On the other hand, CBD does not directly stimulate CB1 and CB2 receptors. CBD interacts with cannabinoid receptors through what scientists call modulation. The indirect effect of CBD on CB1 and CB2 receptors makes it non-psychoactive. [R]
CBD can also stimulate the release of endocannabinoids. By inhibiting the enzymes that break down endocannabinoids, CBD increases the levels of natural cannabinoids in the body. The ability of CBD to influence a wide range of receptors throughout the body is what gives CBD massive therapeutic potential.
CBD vs. THC: psychoactive components
Despite their similar chemical structures, CBD and THC produce different psychoactive effects.
When THC binds to CB1 receptors in the brain, it creates a sense of euphoria and mind-altering effects. CBD does not do that. In fact, the presence of CBD might be able to interfere with the binding action of THC and weaken the psychoactive effects.
THC makes people high, which is why it is often associated with recreational cannabis. CBD, on the other hand, is more valuable for its non-psychoactive therapeutic effects on the physiology of the body and mind.
CBD vs. THC: how they interact with each other
CBD has the ability to modulate the psychotropic effects of THC as it binds with the CB1 receptor. When they work together, CBD is able to reduce some of the side effects of THC such as anxiety, paranoia and short-term memory loss. Evidence suggests that a CBD-rich product with very little THC can produce therapeutic effects without the euphoria.
Despite the evidence of positive interactions between CBD and THC, most products on the market contain either THC or CBD only and not both. Similar to traditional pharmaceuticals, this is probably because medicines with a single active ingredient are easier to develop, test, produce, prescribe and regulate.
However, emerging evidence on the "entourage effect" of whole plant medicine could sway the trend. Advocates of whole plant therapy argue that cannabis should be used in its most natural form possible – containing more than 400 trace compounds. The receptors of the human endocannabinoid system work more efficiently with whole-plant, full spectrum cannabinoids rather than CBD on its own.
CBD vs. THC: health benefits
CBD and THC can provide the same relief for several medical conditions. Some people may prefer to take CBD instead of THC because of the absence of euphoric side effects.
Known effects of THC:
- Analgesic: relieves pain and inflammation
- Relaxation: creates a general state of relaxation
- Drowsiness: helps induce sleep
- Appetite stimulant: creates a strong urge to eat
- Euphoria: creates a sense of high
Known effects of CBD:
- Anti-convulsant: suppresses seizure activity
- Anti-oxidant: fights the effects of free radicals
- Anti-psychotic: combats psychosis
- Neuro-protective: protects and helps regenerate neurons in the brain
- Anti-emetic: reduces nausea and vomiting
- Anti-inflammatory: reduces inflammation
- Anti-tumoral: prevents tumor growth and might even help destroy cancer cells
Primary medical applications of THC:
- Pain relief
- Muscle spasticity
- Sleep apnea
- Stress disorders
- Mitigate side effects of chemotherapy, multiple sclerosis, glaucoma, AIDS, and spinal injuries
- Boost appetite
Primary medical applications of CBD:
- Inflammatory bowel disease
- Mitigate side effects of multiple sclerosis and chemotherapy [R]
In June 2018, the U.S. Food and Drug Administration (FDA) approved the Epidiolex for the treatment of rare, difficult-to-control forms of epilepsy. It is the first prescription medication that contains CBD.
Some experts suggest that a combination of THC and CBD is the most ideal method of treating pain symptoms. This validates theory of the entourage effect. [R]
Do note that taking too much THC could aggravate pain symptoms. THC must be consumed in small doses when used for pain relief.
CBD vs. THC: side effects
Even in large doses, CBD is well tolerated in humans. According to research, any side effects from taking CBD are likely the result of cannabidiol interacting with other medications.
Its sibling however has immediate and long-term cognitive side effects. THC may cause impaired thinking and reasoning, altered decision-making, inability to plan and organize, and lack of control over impulses. [R]
The psychoactive effects of THC include anxiety, panic attacks, paranoia, intensified sensory experiences, time distortion, and altered social behavior. THC overdose can have severe side effects such as agitation, psychosis, delusions, and hallucinations.
THC has also been proven to have acute and long-term negative effects on the parts of the brain that control memory and learning.
Physiologically, THC may induce increased heart rate, dizziness, dry mouth, bloodshot eyes, sedation, vomiting and nausea, coordination problems, slower reaction times, and motor impairment. Severe shaking, uneasiness, and psychotic reactions may result from ingesting too much THC and may require immediate medical attention in the emergency room.
THC is potentially addictive, and long-term use can cause serious side effects to the heart, brain and lungs. [R]
Those who smoke weed could be susceptible to constant colds and coughing, phlegm, and bronchitis. THC can compromise the immune system of the lungs with enlarged bronchial passageways and irritations of the airways, thereby increasing the risk for infection.
Marijuana intake can dramatically increase heart rate – and it stays elevated for around three hours. Not only will cannabis smoking speed up heart rate by 20-100%, it will also raise blood pressure while sitting and drop blood pressure when standing up. Patients who are already suffering from hypertension, heart arrhythmia, and other cardiac diseases could feel worse after consuming marijuana.
THC addiction can also have negative social consequences with strong cravings and seeking out marijuana.
CBD does not cause harmful cognitive effects that are associated with THC. In fact, CBD might be able to counteract the psychoactive effects of THC. [R]
Cannabis plants that contain high THC and low CBD could cause a stronger ‘stoned’ feeling. On the other hand, strains with high CBD and low THC produce a weaker, more relaxed effect.
Given the increasing popularity of medical cannabis, growers are turning their focus on creating strains that contain a higher CBD content to minimize psychoactive side effects.
Research has also shown that CBD is non-toxic and there is no risk of lethal overdose.
A 2011 review on the safety and side-effects of CBD showed that large doses had no effects on blood pressure, body temperature, heart rate, movement, food intake, digestion, motor activity, and embryonic development. [R]
Overall, the lower health risks of CBD combined with its high efficiency in treating various health conditions make it a better candidate for natural therapeutic applications than THC. [R]
CBD vs. THC: legal status
Cannabis laws in the United States are constantly evolving. Marijuana and THC are included on the list of controlled substances, so they are illegal under federal law.
However, 20 states plus Washington D.C. have legalized medical marijuana as long as it is prescribed by a licensed physician.
In states where marijuana is legal for recreational or medical purposes, you should be able to buy CBD with no issues. Few states have passed laws that make medical CBD legal.
CBD is also found in hemp, which is legal in all 50 states. Many companies have taken advantage of this loophole by importing high-CBD hemp extracts instead of sourcing from marijuana growers.
Before you try to buy CBD or THC, read about your state laws.
CBD vs. THC: drug testing
Because cannabinoids are stored in the fat cells of the body, THC can show up on drug tests even after several days or weeks.
Most standard drug tests can spot chemicals related to THC so it will always show up on a screening. Not every drug test will be able to detect CBD but there are tests that may be sensitive to CBD.
Do note that industrial hemp is classified as containing less than 0.3% of THC so there could still be some traces of the compound. You might test positive for THC even if you have not used it.
Does CBD oil contain THC?
Both marijuana and hemp contain CBD and THC. Marijuana has a higher concentration of THC while hemp has a higher concentration of CBD. Because hemp contains more CBD than THC, it is the best source for extracting CBD oil.
The average marijuana strain contains about 12 percent of THC. Hemp can have no more than 0.3 percent of THC. Because THC is present in the hemp plant, CBD oil may contain a small amount of THC.
Cannabis has been around for thousands of years, treating various ailments across cultures around the world. Restrictions and regulations, however, have slowed down and limited the pursuit of scientific research into the therapeutic effects of cannabinoids. As more countries start to legalize cannabis, scientists are now beginning to unearth the vast potential of this plant and its applications in modern medicine.
In October 2017, the World Health Organization (WHO) published a report on the potential clinical uses of CBD. There is now unequivocal evidence that CBD may be effective in the treatment of some forms of epilepsy including Dravet syndrome – a severe form of childhood epilepsy associated with drug-resistant seizures and high mortality rates. Clinical and pre-clinical studies have also demonstrated that CBD has analgesic, anti-inflammatory, anxiolytic, antipsychotic, neuroprotective, hypoxia-ischemia, and anti-tumor properties. [R]
The WHO added that patients suffering from Alzheimer’s disease, Parkinson’s disease, and Huntington’s disease as well as multiple sclerosis, psychosis, anxiety, depression, and cancer might be able to benefit from treatment with CBD.
The FDA has already approved two drugs containing THC and its synthetic version.
Dronabinol (Marinol®) is a gelatine capsule that contains THC. It is administered orally to treat nausea and vomiting caused by chemotherapy. It also helps with poor appetite and weight loss in patients suffering from AIDS.
Nabilone (Cesamet®) contains a synthetic version of THC that is able to ease chemotherapy-related nausea and vomiting that cannot be treated with other drugs.
A third drug – Nabiximols (Sativex®) – is currently under review in the United States. This mouth spray contains a one to one ratio of whole-plant THC and CBD extracts. Sativex® is already available in Canada, Australia, the United Kingdom, Spain and 25 other countries for the treatment of muscle spasms from multiple sclerosis as well as cancer pain.
CBD and THC have exhibited great potential in reducing symptoms associated with a wide range of medical conditions. Before trying hemp CBD, talk to your healthcare provider. Some drugs do not interact well with cannabinoids so you should consider the possibility of side effects if you are currently on medication. If you do not want any of the acute and long-term adverse effects associated with THC, then stick to CBD-rich supplements.