Cannabidiol (CBD): What Does It Do and How Does It Affect the Brain & Body?

Cannabidiol (CBD): What Does It Do and How Does It Affect the Brain & Body?

Published on September 7, 2021 by Kristina Willis

As medical professionals bear witness every day, there is a desperate need for medications to treat the plethora of dangerous and debilitating diseases that plague the human population. Unfortunately, many of today’s drugs can cause harmful side effects, including dependency and addiction. Due to its strong safety profile and range of therapeutic attributes, cannabidiol (CBD) makes the list of promising substances to be wielded for medicinal purposes.

CBD is a non-psychoactive compound found in the cannabis sativa plant. Like other cannabinoids, CBD interacts with the endocannabinoid system (ECS) to produce changes in the body and brain. Thanks to its many therapeutic properties, it may prove to be an invaluable tool for addressing numerous medical conditions.

Though CBD was first identified in 1940, much remains to be discovered about how it works and its potential benefits. Further investigation is warranted to fully understand everything that CBD is capable of.

Before getting into the complexities, it is helpful to have a basic understanding of how CBD affects the brain and body.


What Is CBD?

CBD is the second most prevalent active ingredient out of more than a hundred cannabinoids found in the cannabis sativa plant.

The amount of each compound depends on the type of cannabis it comes from. For instance, hemp contains high CBD and low THC concentrations, while marijuana has high THC and low CBD.

How Is CBD Different From THC?

THC can produce psychotic symptoms, anxiety, and increased heart rate; however, CBD has no physiological effects. Moreover, CBD does not provoke the euphoric high that is typically associated with recreational cannabis use. In fact, CBD is even able to counteract or reduce the psychoactive effects of THC.

Though used for both, THC is generally cultivated for recreational purposes, while CBD is primarily medicinal. However, they are often used in conjunction with one another to produce a desired effect. For instance, when taken individually, THC is more effective for treating symptoms of Crohn’s disease, but a combination of THC and CBD produces the best results.

Though both affect the ECS, THC works by binding directly with the C1 and C2 receptors, while CBD interacts with enzymes, transporters, and proteins.


How Does CBD Affect the Body?

Cannabis compounds affect the body by interacting with the ECS—a system responsible for regulating many of the body’s processes. Like endocannabinoids (those produced naturally by the body), phytocannabinoids (those produced by plants) can interact with cannabinoid receptors to illicit a bodily reaction.

Though there are other suspected receptors, current understanding deals primarily with the CB1 and CB2 receptors. Instead of binding to these receptors, CBD interacts with the ECS indirectly to influence physiological systems typically regulated by the ECS. For instance, CBD acts as a CB2 antagonist and inhibits the production of cytokine proteins, effectively reducing inflammatory responses in the affected region.


How Does CBD Affect the Brain?

Cannabinoid receptors are not only found throughout the body; they are also in the brain. Additionally, preclinical evidence and animal models suggest that CBD might influence other receptors related to behavior and cognition. For example, a single dose of CBD may help modulate neurotransmitter activity such as serotonin production.

Studies have also found that CBD can affect brain connectivity during activity and while in a resting state. In addition, by modulating and restoring imbalances in the limbic system, CBD can help inhibit emotional and response processing. For instance, CBD is widely used to treat anxiety and may even prevent the formation of bad memories associated with the onset of PTSD.

There is also evidence that CBD can decrease the risk of substance use disorders and developing psychosis by down-regulating CB1 receptors in the brain. However, further research is needed to understand precisely how CBD affects the brain and how it might be used to control specific processes.

Image by Ars Electronica licensed under CC BY-NC-ND 2.0


Is CBD Safe?

“Across a number of controlled and open label trials CBD of the potential therapeutic effects of CBD it is generally well tolerated, with a good safety profile.”

—World Health Organization

According to global health organizations, CBD has an excellent safety profile. Unlike THC, CBD shows no evidence of eliciting tolerance or physical dependence issues. Compared to other drugs, the risk of using CBD is relatively low.

3 Safety Concerns with Using CBD

1. Lack of regulation

The biggest safety problem with CBD is the lack of accountability regarding products that contain it. Since the FDA does not regulate CBD supplements, it is difficult for consumers to know exactly what they are buying. A 2017 study found that almost 70% of online CBD products were mislabeled and contained higher or lower concentrations of CBD. Moreover, 20% had detectable THC levels.

Even when products feature labels, there is no guarantee that the listed dose, ratios, or active ingredients are accurate. Manufacturers are free to make unsubstantiated claims, such as proclaiming that their product is a cure-all for serious illnesses that require medical attention. Such misleading information can be dangerous to consumers.

2. Dosage unfamiliarity

Though evidence exists to support the beneficiary effects of cannabis, not much is known about dosing. The clinical studies essential for determining correct dosages are currently lacking. Taking too much may cause adverse side effects, while taking too little may fail to produce any results.

CBD is often used as a form of self-medication, which is particularly problematic considering the lack of dosage information currently available to the public. Before self-medicating with cannabis, talk to your doctor about a prescription for an appropriate dosage. 

3. Interaction with other medications

Pure CBD may be safe when taken in isolation, but unfortunately, there is little information regarding its interaction with other medications. CBD inhibits enzymes in the liver that break down drugs and toxins. Therefore, taking CBD in conjunction with other drug therapies may hinder the body’s ability to metabolize or remove other substances.

What Are the Side Effects of CBD?

CBD is considered safe and does not pose any kind of public health threat; however, that does not mean that there are no drawbacks to chronic use. Though medically insignificant, one out of every three users experiences some kind of non-serious side-effect.


Side effects of CBD include:

► Nausea
► Fatigue
► Irritability
► Diarrhea
► Dry mouth
► Reduced appetite


What Are the Medicinal Benefits of CBD?

Preclinical research seems to affirm anecdotal accounts that CBD can provide a broad range of therapeutic effects, including antioxidant, anti-inflammatory, analgesic, and anti-psychotic properties. 62% of respondents to an online survey reported using CBD to treat a medical condition. The three most common ailments were pain, anxiety, and depression.

Though studies are currently in their infancy, many theorize that CBD’s anti-inflammatory characteristics may be useful to treat a wide variety of diseases and conditions.

What Medical Conditions Can CBD Help?

Investigations into CBD’s benefits and limitations are ongoing. Clinical trials are currently testing its neuroprotective effects and anti-cancer properties. Presently, there is only one FDA-approved CBD drug called Epidiolex, which treats severe forms of epilepsy. CBD also shows potential as a means to treat drug addiction, though more research is required.


Diseases with a strong positive correlation to cannabis treatment:

► Childhood seizure disorders
► Alzheimer’s disease
► Parkinson’s disease
► Multiple sclerosis
► Huntington’s disease
► Rheumatoid arthritis
► COVID-19 inflammation


Is CBD Legal?

In 2018, congress passed the Hemp Farming Act of 2018, which legalized hemp with less than 0.3% THC. Removing CBD from the categorization of a Schedule I drug has created the means for studying it. Moreover, medical professionals who prescribe or suggest medical cannabis as a treatment are protected by law.


Who Can CBD Help?

CBD has the potential to help a lot of people suffering from debilitating conditions that affect the mind and body. The ECS system is responsible for regulating a broad range of functions such as memory, sleep, and mood—to name a few. CBD’s ability to influence the ECS could significantly relieve symptoms involving essential processes.

When it comes down to it, CBD shows a lot of potential as a medicinal drug. With an excellent safety profile and a whole slew of therapeutic properties, there’s not much more you can ask for other than hard evidence from placebo-controlled clinical trials. Fortunately, those are underway, and results from the upcoming years will reveal valuable insight into potential treatments and side effects.

For now, consult your doctor before starting any kind of frequent CBD regimen. Though deemed safe, there is still some uncertainty about how it may react with other medications and treatments. Your doctor can properly advise you on health matters and keep an eye on your mental and physical condition.