What We Know About CBD (Cannabidiol): The Latest Research on Uses, Benefits, and Side Effects.
You may have heard about the somewhat controversial substance that is cannabidiol (or CBD). Due to it's potent anti-inflammatory effects, CBD has made it's way into complementary and alternative medicine for the management of many different conditions.
CBD is one of the many substances found in the cannabis plant known as cannabinoids. Along with many other cannabinoids, CBD is a non-psychoactive component of cannabis; the psychoactive portion is known as tetrahydrocannabidiol (THC). This means that the extract of CBD does not affect mental status and does not cause the "high" attributed to THC. It does, however, provide anti-inflammatory properties and other factors which appear to give some benefits without the negative side effects that may be seen with consumption of the whole plant (1).
In the United States, CBD products derived from industrial hemp (without THC) are legal and use in every day products is increasing. CBD may be found in many supplements and health products like topical creams, pills, tinctures, oils, oral/nasal sprays, even food & beverages. Products are commonly prescribed by physicians or sold online or in health stores.
How Does CBD work?
CBD exerts its action on the endocannabinoid system; a complex network of receptors in the brain, nervous system, and immune system. Under normal conditions the body makes it's own (endogenous) cannabinoids to activate the receptors in this system which controls cellular communication and regulates processes like inflammation, mood, pain sensitivity, sleep, and many others (2) . CBD consumed from outside the body (exogenous) exerts a similar action on endocannabinoid receptors.
What are the potential risks of CBD?
CBD appears to be safe in most instances, but more research is needed to confirm or refute it's safety (1). Many studies suggests that CBD is non-toxic, does not have an effect on food intake, does not affect digestive motility, does not alter psychological function, and does not affect heart rate, blood pressure, or body temperature (3).
Some studies do note that CBD administration can cause certain drug interactions by affecting their metabolism in the liver and have some side effects related to fertility (3).
Due to some of the unknowns about CBD use and it's varying effects from person-to-person, it is extremely important to consult a trained healthcare provider if you are considering the use of a CBD product.
Some additional side effects that have been noted with CBD use include the following: anxiety, nausea, vomiting, appetite change, diarrhea, dizziness, and drowsiness.
What are the potential benefits of CBD?
It is important to note that potential benefits of CBD use are not well-documented in human trials and much of the research is in animal studies or experimental lab conditions. Much more research in humans is needed before CBD can be confirmed or refuted as a treatment for any condition. The following only represents potential therapeutic benefits in early research on CBD alone.
1. Reduce Inflammation & Oxidative Stress:
The ability of CBD to activate anti-inflammatory receptors is well-documented in many conditions. It also appears to blunt oxidative stress from harmful free radical formation. This may provide benefit in many chronic disease states by lowering long-term systemic inflammation (4)
Conditions that may benefit from the anti-inflammatory effects of CBD include the following:
Neurological Diseases - Epilepsy, Alzheimers, Multiple Sclerosis, etc. (7, 8, 9, 10)
Substance Abuse Treatment (11)
Acne (13)
2. Anxiety and Depressive Disorders:
Anxiety and depressive disorders are widespread throughout the United States, making them a top target for pharmacological development. Medications for these disorders have not shown great efficacy and there are many potentially severe side effects that are associated. Although CBD does not have a psychoactive component, it still may be an effective option for anxiety and depression.
A recent scientific review noted that human evidence strongly supports the use of CBD for anxiety disorders. This review mentioned evidence showing CBD to be effective for the following disorders (12):
Post-Traumatic Stress Disorder (PTSD)
Generalized Anxiety Disorder (GAD)
Panic Disorder (PD)
Obsessive Compulsive Disorder (OCD)
Seasonal Affective Disorder (SAD)
3. Pain Relief:
Marijuana has been used for the treatment of pain for centuries and now the CBD portion of the plant is beginning to show some benefits for pain relief as well. CBD is becoming more common as a therapeutic option in some athletes who are looking to reduce muscle pain and inflammation from training and competition.
Through it's ability stimulate the endocannabinoid system and it's effects on inflammation, CBD could also potentially reduce pain caused by many conditions.
The use of CBD with the psychoactive THC component has been shown in animal studies to be beneficial for nerve pain from conditions like multiple sclerosis, diabetes, and nerve injury. It is also noted that due to it's ability to regulate both inflammation and the immune system, CBD has potential for treating pain from rheumatoid arthritis (13).
Although not well-studied for musculoskeletal pain and stiffness, CBD use is popular for these symptoms and many people claim that it may help.
4. Cardiovascular Health
The constriction of blood vessels is one of the ways that blood pressure may become elevated. CBD has been shown to have a relaxing effect on arteries. This, along with it's anti-inflammatory properties may potentially benefit cardiovascular health. Animal studies have shown the ability of CBD to protect against heart disease related to diabetes and increase blood flow following a stroke. Due to these benefits, a study in the British Journal or Clinical Pharmacology suggested that CBD could potentially be a therapeutic option for cardiovascular disease pending more research (14).
In addition to this animal data, a smaller study in humans demonstrated that 600mg of CBD reduces resting heart rate and lowers the blood pressure increase which is normally seen with exercise (15).
5. Symptoms Associated with Cancer
Both CBD and THC are popular research topics in cancer treatment, prevention, and side effect management. Although not demonstrated in humans as a reliable cancer treatment or preventative option, CBD has been shown to slow growth/kill cancer cells without harming healthy cells in laboratory dishes (R).
CBD has some evidence for it's ability to manage the associated side effects of cancer and it's conventional treatment. Nausea and vomiting are common side effects of chemotherapy and studies have demonstrated that CBD may be an effective treatment for these side effects (16)
Overall
Therapeutic CBD use can be defined with one word: potential. There is not quite enough research to confirm many of the claims but the preclinical data shows extremely promising results.
Those against cannabis use due to the psychoactive component THC should not worry. Although from the same plant, CBD does not cause a "high" or any cognition changes attributed to THC.
Many health conditions may benefit from CBD use but it also could potentially cause some minor side effects. It is essential to consult a knowledgeable healthcare provider beginning any new supplement or product, including CBD.