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CBD is a cannabinoid which has no altering effects on consciousness, but it does induce relaxation, sleepiness, and pain relief. It can be taken in many forms – form food and sweets supplemented with CBD, to capsules, tinctures, lotions, and vaping oil.
In the US, CBD oil derived from industrial hemp has been legal under federal law since 2014. The one derived from the marijuana plant is still illegal because it contains high levels of THC.
CBD oil is believed to have many benefits against pain, stress, depression, sleep problems, and more, which ensured its popularity. However, it carries a number of side effects and health risks. FDA has recently issued a public statement about products containing CBD and illegal marketing of the products for which producers claim to be remedies for many ailments and serious illnesses.
What is CBD oil and how does it affect the brain?
CBD is short for ‘cannabidiol’. It is commonly found in the cannabis plant and falls under the category of compounds known as cannabinoids. In the human nerve cells, there are receptors that react with cannabinoids – these receptors are a part of the endocannabinoid system – which has many roles related to the internal balance of the body (homeostasis). Some of them are roles in mood and memory, appetite control, the feeling of pain, and sleep cycles and circadian rhythm.
Endocannabinoids are a type of cannabinoids which is naturally produced in the body. Their receptors easily get attached to other cannabinoids, a process which interferes with the natural processes. Although this can be helpful in relaxation purposes, too much may lead to unwanted consequences.
Unlike the most popular of the group – THC (tetrahydrocannabinol), CBD doesn’t lead to intoxication or change one’s perception. It offers relaxation (although still not researched enough in humans) and pain relief. Another very important benefit is a good night’s sleep which CBD can help promote.
Where does CBD oil come from?
CBD oil is mainly extracted from industrial hemp. In order to separate CBD from the plant, certain extraction solvents are used. CBD is then tested and thermally treated, making it more compatible with the human body.
CBD oil can be found in two forms in the US. One is pure CBD, and one is CBD which contains other cannabinoids. The first one is called crystalline isolate and the second is full spectrum CBD (whole plant CBD).
Whole plant CBD contains many cannabinoids, including THC (maximum 0.3% – which is federally a legal boundary for THC presence). This type has shown much better results in treating inflammation and anxiety in mice, whereas pure CBD has failed to yield the same effects. Researchers assume that many cannabinoids react among themselves, which allows them to have a different reaction.
The whole plant shouldn’t be used prior to drug tests as THC in them, even though in tiny amounts, may test positive.
FDA warns about CBD products
In a statement released on December 20, 2018, FDA expresses concern about the widespread interest and use of CBD. They highlight that CBD, just like THC, is a drug which has yet to undergo human trials.
As there is an increasing number of products which claim to cure, mitigate or treat various diseases, FDA insists each of them has to undergo testing and become FDA-approved in order to be legally allowed to market as a drug.
They also inform the public that “it’s unlawful under the FD&C Act to introduce food containing added CBD or THC into interstate commerce, or to market CBD or THC products as, or in, dietary supplements, regardless of whether the substances are hemp-derived”. They also warn that it is illegal to market active drug ingredients as food supplements.
Please look at the letters of warning sent by FDA to companies which advertised their products as remedies for cancer, Alzheimer’s disease, or other serious illnesses, without ever being properly tested.
What are the uses of CBD oil?
Clinically, CBD oil seems to be the most successful in treating epilepsy – in fact, it is supported by a large body of evidence and approved by the FDA for this purpose.
Its anti-inflammatory effect is collecting more and more support, but mainly from animal studies. Some lotions claiming to treat acne contain CBD which allegedly appeases inflamed skin.
A study based on a small number of patients with multiple sclerosis has shown promising results in relieving pain, when administered on the skin, through a buccal spray.
However, most of the claimed properties of CBD oil, like cancer, heart disease treatment, and irritable bowel syndrome (IBS) have only gone through the first stages of animal testing. What they usually give us is a recommendation for further research and not solid evidence.
Unfortunately, research that may offer hope for future treatments (or fail to produce any results) is often abused by companies which aim to make a profit. This substance is yet to be tested – including both, its benefits and risks.
CBD oil and sleep
As mentioned above, CBD can cause pain relief in humans. This also means it can help treat insomnia because many patients who are under constant stress often can’t fall or stay asleep. A study showed that about 50% of patients suffering from cancer, arthritis, or various other pain-causing conditions has seen a huge increase in sleep quality over the course of four years they have taken the CBD medicine.
Causes for concern
There is not enough evidence on long-term consequences of CBD on the human brain. Most of the studies were performed on animals, and scientists have yet to find out the actual benefits and risks. It is unclear how CBD would affect children, pregnant women and their babies, hormones, immunity, and the endocannabinoid system. Risks of consuming high dosages are unclear.
Many untested and unapproved products can be found on the market, so a prospective consumer should be very careful about what they’re buying.
There is a possibility that CBD oil may interfere with the metabolization of medications.
CBD oil side effects
So far, no dangerous side effects of CBD have been reported. Most of them are mild and include effects similar to those of other cannabinoids:
- interference with appetite (increasing food cravings and intake),
- dry mouth feeling (increasing thirst),
- lowering blood pressure (which might lead to lightheadedness),
- tiredness (as a result of relaxation and low blood pressure),
- diarrhea (only when CBD is taken in excessive amounts).
CBD oil usage
When administered on the skin, as a lotion, spray or ointment, CBD can be very effective in reducing pain or muscle tension.
Taken orally, in the form of oil, food, or capsules, CBD may not be so effective. According to Marcel Bonn-Miller, Ph.D. and assistant professor from the University of Pennsylvania School of Medicine, less than 20% of the CBD we intake is actually absorbed.
CBD oils are also available as vape oils, which ensure the substance gets directly into lungs. Whether CBD vape oils are healthy or not is yet to be tested.
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- Statement from FDA Commissioner Scott Gottlieb, M.D., on signing of the Agriculture Improvement Act and the agency’s regulation of products containing cannabis and cannabis-derived compounds. FDA. December 20, 2018.
- https://www.fda.gov/newsevents/newsroom/pressAnnouncements/ucm628988.htm Accessed March 23, 2019.
- FDA approves first drug comprised of an active ingredient derived from marijuana to treat rare, severe forms of epilepsy. FDA. June 25, 2018. https://www.fda.gov/newsevents/newsroom/pressannouncements/ucm611046.htm Accessed March 23, 2019.
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- Thompson, D. CBD Oil: All the Rage, But Is It Really Safe and Effective? Health Day. May 7, 2018. https://consumer.healthday.com/public-health-information-30/marijuana-news-759/cbd-oil-all-the-rage-but-is-it-really-safe-and-effective-733556.html Accessed March 23, 2019.