• Cannabidiol (CBD) is a naturally occuring active ingredient of the cannabis plant. Unlike tetrahydrocannabinol (THC), CBD does not produce mind-altering effects. 
  • There are three types of CBD oil products: full-spectrum, broad-spectrum, and CBD isolates. They may be taken through sublingual, ingestion, inhalation, or topical methods. 
  • CBD interacts with the body’s endocannabinoid system (ECS) and its cannabinoid receptors to maintain a state of balance and promote overall wellness
  • Multiple studies have suggested that CBD has potential health benefits that may help with various conditions, including epilepsy, pain and inflammation, insomnia, anxiety and depression, neurological disorders, and cancer-related symptoms(1).
  • Although CBD is generally safe and well-tolerated, it may cause side effects, such as nausea, vomiting, drowsiness, diarrhea, and fatigue. CBD may also interact with other drugs or supplements currently taken(2).
  • The Farm Bill of 2018 legalized hemp cultivation and the transfer of hemp-derived products across state lines for commercial or other purposes. All 50 states have their own laws with varying degrees of restriction(3). 

What is CBD Oil

The cannabis plant can be categorized into three varieties: sativa, indica and ruderalis. Cannabidiol (CBD) is one of the most prominent compounds in over 100 known cannabinoids found in the Cannabis sativa plant. 

CBD is extracted from the hemp plant, which is closely related to the marijuana plant. However, unlike marijuana, CBD does not contain tetrahydrocannabinol (THC) because it is a separate cannabinoid.

THC is the main psychoactive cannabinoid found in the cannabis plant, which causes the sensation of getting “high.” THC is often associated with medical marijuana (medical cannabis)

Another chemical in marijuana (cannabis) that has therapeutic health effects is CBD. Due to its promising benefits and non-psychoactive effects, CBD has gained popularity among people seeking a natural alternative to conventional treatments. 

CBD is widely studied due to its potential anti-inflammatory and neuroprotective properties(4)

According to a report from the World Health Organization, “In humans, CBD exhibits no effects indicative of any abuse or dependence potential…. To date, there is no evidence of public health-related problems associated with the use of pure CBD(5).”

CBD is one of the several identified phytocannabinoids found in the cannabis plant, along with cannabinol (CBN) and cannabigerol (CBG). 

A phytocannabinoid is a cannabinoid that naturally synthesizes in plants, and each one has a unique effect.

Some of the most common types include the following:

  • Cannabinol (CBN) – It is a cannabinoid produced separately from oxidized THC. CBN is mildly psychoactive and induces sedative effects(6).
  • Cannabigerol (CBG) – It is a non-intoxicating cannabinoid that may contain antibacterial properties. Research has suggested CBG may be useful for reducing inflammation and slowing the growth of cancer cells and tumors(7)
  • Tetrahydrocannabinolic Acid (THCA) – It is one of the main ingredients found in raw cannabis and the precursor to THC. Similar to other acidic cannabinoids, THCA contains anti-inflammatory properties that may be useful for cell proliferation and reducing spasms(8).

Differences between CBD and THC

Both CBD and THC have the same chemical formula of 21 carbon atoms, 30 hydrogen atoms, and two oxygen atoms(9)

The slight difference lies in how these atoms are arranged. CBD and THC‘s different arrangement of chemical properties accounts for their varying effects in the body. 

CBD and THC are chemically similar to the endocannabinoids found in the body. It allows the two compounds to interact with the cannabinoid receptors.

This interaction affects the release of neurotransmitters in the brain. Neurotransmitters are responsible for relaying messages between cells.

These chemicals also have roles in pain, mood, stress, immune system, memory, and sleep(10)

Studies have suggested that CBD may help with inflammation and neuropathic pain, while THC may be beneficial for spasticity and cramp-related pain(11).

Types of CBD

Full-Spectrum CBD

Full-spectrum CBD contains all cannabinoids naturally found in the cannabis plant, including THC, terpenes, flavonoids, and fatty acids. This type of CBD is often called a full or whole plant extract. 

Full-spectrum extracts go through the cannabinoid extraction process and filtration. However, none of the cannabinoids are removed from the extract. 

While full-spectrum CBD products contain THC, the trace amount of less than 0.3 percent is not enough to get an individual high but may show up in a drug screen. 

The chemical compounds and cannabinoids in a whole-plant extract are known to have healing properties. 

These cannabinoids help enhance the overall benefits of full-spectrum CBD oil. For instance, the terpenes in the cannabis plant are found to have anti-inflammatory properties(12)

A 2005 study concluded that CBD with full-spectrum CBD extract had greater medicinal properties than pure CBD(13). The higher concentrations of cannabinoids and terpenes in the CBD oil work together to create an “entourage effect.” 

Research has shown that the entourage effect might help increase potency and maximize the therapeutic benefits of the hemp plant(14)

Broad-Spectrum CBD

Broad-spectrum CBD is the middle ground between full-spectrum CBD oils and pure CBD isolates

This type of CBD contains multiple cannabinoids and other chemical compounds in the cannabis plant, except for THC

Like other types, broad-spectrum CBD goes through the normal extraction process. However, the THC is removed from the extract. 

The vitamins, minerals, fatty acids, and other cannabinoids remain in the broad-spectrum extract. These compounds may continue to produce the entourage effect.

Broad-spectrum may be optimal for athletes and patients who cannot consume THC

CBD Isolates

CBD isolate is the purest form of CBD, as it only contains cannabidiol. Isolates do not contain any other cannabinoids, terpenes, or fatty acids from the hemp plant

Containing up to 99% CBD, CBD isolates provide maximum CBD concentration(15). This type of CBD is sold as a crystal, powder, or oil. 

CBD isolates are made through the same extraction process as other CBD oils. However, the CBD is filtered out once the cannabinoids are extracted. 

CBD then goes through winterization, a chilling process that removes all other chemical compounds.  

CBD isolates are generally cheaper, and they have no THC. However, this type of CBD does not provide the potential entourage effect that exists when full-spectrum cannabinoids are present. 

How CBD Works in the Body

CBD interacts with the brain and body and produces effects through several different mechanisms. 

Upon entering the human body, CBD interacts with the central nervous system and a wide range of proteins. 

A key part of this interaction takes place within the body’s endocannabinoid system (ECS), a biological network comprised of endocannabinoids (endogenous cannabinoids), cannabinoid receptors, and the enzymes that synthesize the endocannabinoids.

 The two central cannabinoid receptors in the ECS are CB1 and CB2.

CB1 receptors are mostly found throughout the body, particularly the brain. These receptors are responsible for movement, emotion, mood, thinking, memories, pain, appetite, and other cognitive functions(16).

CB2 receptors are predominantly located in the immune system. These receptors affect pain and inflammation(17).

Interestingly, CBD molecules do not attach directly to CB1 or CB2 receptors, rather they modify those receptors’ activity in a way that is not yet understood. Meanwhile, THC attaches to both CB receptors. When these cannabinoids interact with these connectors, they transmit signals that travel through the cells and affect different organs of the body. 

Although CBD does not bind directly to CB receptors, it can modify the connectors’ interactions with THC and act as a blockade against other molecules. 

CBD also interacts with the serotonin receptor 5-HT1A and vanilloid receptor TRPV1(18). These are the other receptor proteins not directly related to the ECS.

The widely perceived pain-relieving and anti-inflammatory properties of CBD may stem from the activation of these additional biological pathways. 

CBD Oil vs. Hemp Oil

Hempseed oil, or hemp oil, is extracted from the seeds of the Cannabis sativa plant. This type of oil does not contain the same levels of compounds in CBD oil. 

However, hemp oil is rich in vitamin E, protein, omega fatty acids, and bioactive compounds beneficial to the body(19)

Hemp oil can only be extracted from industrial hemp. The extraction of the oil requires pressing, processing, and refining of the seeds before they are bottled. 

Cannabidiol oil is also obtained from the hemp plant. However, unlike hemp oil, CBD can be extracted from  either a cannabis plant (marijuana) or hemp plant. 

Typically, CBD oil is extracted from hemp, which is naturally high in CBD. CBD oil is extracted from the leaves, stems, flowers, and stalks of the plant. 

The most popular extraction methods used are carbon dioxide (CO2) and ethanol. 

Methods of Delivering CBD

Although the usual CBD formulation is oil, CBD may come in various forms. These include tinctures, gummies, edibles, capsules, vape, and topicals

CBD oil products are usually made with cannabidiol extracts from the cannabis plant. Then, CBD is diluted with carrier oils, such as hempseed oil or coconut oil.

One of the most common carrier oils used for CBD is MCT (medium-chain triglycerides) oil. MCT is a type of fatty acid that provides quick metabolization and absorption. 

Rather than becoming stored as fat, the calories inside MCT are also burned more efficiently(20)

Each CBD product form has a corresponding method of delivery, depending on the users’ specific needs and preferences. 

Delivery methods also vary in bioavailability, which is the body’s absorption of CBD from the application area into the bloodstream.

When bioavailability is maximized, CBD is more readily available to use, and the body feels its significant effects. 

Sublingual Method

CBD oil tinctures may be consumed sublingually by placing a few drops of CBD oil under the tongue with a dropper. This method is one of the easiest and quickest ways of reaping the potential benefits of CBD.

However, it is important to hold the oil under the tongue for a few seconds before swallowing. 

By holding the CBD oil under the tongue, CBD is absorbed by the mucous membranes found in the mouth and bypasses the digestive system and liver. It allows for faster absorption of CBD directly into the bloodstream. 

In this method, CBD gets into one’s system in about 15 to 30 minutes, while the effects may last for a few hours(21)

Ingesting CBD

CBD may be ingested through CBD gummies, edibles, and capsules. Compared to the sublingual method, ingestion takes much longer to get CBD into the bloodstream. 

Instead, CBD passes through the digestive tract and on to the liver, where it is broken down before it reaches the bloodstream.

Studies showed that CBD undergoes the “first pass effect” when its compounds are metabolized by the liver(22)

In the “first pass effect,” the liver enzymes reduce CBD concentration, and the remainder is sent to the bloodstream and circulated throughout the body. 

When ingesting CBD, it typically takes around 30 to 60 minutes before the effects of CBD are felt(23)

Inhalation of CBD

Inhaling CBD through vape oils may deliver fast-acting effects for those in need of quick relief. When CBD is vaped or smoked, CBD is sent directly to the lungs, where it is rapidly absorbed into the bloodstream and circulated throughout the body. 

CBD reaches peak concentrations within three minutes, causing the effects to be felt shortly after consumption. However, the effects last for a few hours only.

Despite being an effective method of delivery, vaping has different side effects. These include coughing, dry mouth and throat, and shortness of breath(24). Vaping may not be appropriate for everyone and carries health risks.

Studies showed that lung diseases and injuries, such as collapsed lung and lipoid pneumonia, are associated with vape use(25).

Topical Application

CBD-infused topicals come in various forms, such as lotions, creams, balms, gels, sprays, and roll-ons. These products are applied directly to the skin to relieve muscle and joint pain(26) or treat some skin conditions, such as psoriasis and eczema(27)

CBD is absorbed through the skin’s surface and interacts with localized cannabinoid receptors. However, there is insufficient data to determine the efficacy of topical CBD. 

However, compared to other methods, topicals have a low absorption rate, which is not enough to reach the bloodstream. When CBD is applied topically, it may take effect at about 90 minutes(28)

Aside from CBD, topicals also include pain-relieving ingredients, such as menthol, camphor, or anti-inflammatory cannabinoids, like THCA(29).

CBD Dosage

The amount of CBD depends on different variables, including age, height, weight, genetics, and intended use. 

The onset time or the time it takes before CBD starts working in the body may also vary from person to person. 

The following factors must be considered when finding the right CBD dosage.

Body Weight 

A person’s body weight and mass have a significant impact on how the body consumes any substance. 

Similarly, the amount of body fat influences the amount of CBD one needs for the compound to be effective.  A larger body mass requires more CBD for its effects to be felt. 

A person’s body weight and mass also affect how long CBD stays in the system. 

Metabolic Rate

The time it takes for CBD to remain in one’s system also depends on one’s metabolic rate. 

The body’s metabolism determines how long it takes to synthesize and break down CBD compounds, affecting how quickly the body processes CBD. 

CBD Quality and Frequency of Use

The quality of the CBD product and how often it is used also influences how long CBD takes to work. 

Finding the optimal dose depends on the type of product, the amount of CBD inside it, and the specific condition it is used for. 

Generally, one should start with a low dose when taking CBD for the first time. CBD users should observe their body’s reaction to the CBD and note if there are any side effects

Once the body gets used to CBD, the individual may gradually increase the dosage. Determining the right dosage helps one maximize CBD’s potential benefits. 

It is advisable to consult a medical professional first to determine the appropriate dosage. A physician can also advise if CBD may be used by an individual with preexisting medical conditions. Never attempt to self-diagnose or self-treat.

Uses and Potential Health Benefits of CBD

CBD vs. Epilepsy

There is strong scientific evidence for CBD’s effectiveness in treating childhood epilepsy syndromes, such as Lennox-Gastaut syndrome (LGS) and Dravet syndrome

These two rare forms of epilepsy do not typically respond to anti-seizure medications. 

However, numerous studies showed that CBD helped reduce the frequency or number of seizures(30). In some cases, CBD helped stop the seizures altogether. 

Scientists began to understand how CBD prevents seizures without the side effects of previously used medications(31)

After years of research into CBD’s safety and effectiveness, the U.S. Food and Drug Administration (FDA) approved the use of Epidiolex in 2018(32)

Epidiolex is a prescription drug derived from a purified form of CBD. Currently, it is the only product approved by the FDA as a treatment for epilepsy

CBD vs. Inflammation and Pain 

Pain and stiffness are often relieved by conventional drugs. However, CBD has been emerging at the forefront as a natural alternative to pain medications. 

Studies have shown that CBD has analgesic and anti-inflammatory properties that may help reduce chronic pain(33). The two most difficult types of chronic pain to treat are inflammatory and neuropathic pain. 

CBD works by impacting endocannabinoid receptor activity, interacting with neurotransmitters, and reducing inflammation. 

A study on rats concluded that injecting CBD reduced pain response to surgical incision(34). Another study also found that oral CBD treatment significantly reduced sciatic nerve pain and inflammation in rats(35).

An animal study from the European Journal of Pain showed that CBD could help lower inflammation and pain due to arthritis when applied to the skin(36)

Aside from animal studies, multiple human studies suggested CBD’s potential for treating pain. Research has found that a combination of CBD and THC is an effective treatment for pain related to multiple sclerosis

Sativex, an oral spray that consists of CBD and THC, may help reduce muscle spasticity resistant to medications(37)

In a 2017 study, 47 people with multiple sclerosis took Sativex for one month and examined its effects. The participants reported improvements in the way they walk, as they experienced reduced pain and muscle spasms(38)

Moreover, after using Sativex, 58 people with rheumatoid arthritis experienced better sleep quality and reduced pain when active(39)

Although results are promising, more human studies are needed to substantiate the claims about CBD’s use for pain relief.

CBD vs. Depression and Anxiety Disorders

A 2017 study reported that approximately 792 million people were living with a mental health disorder(40). CBD has shown promise in initial studies as a treatment for common mental health disorders, such as anxiety and depression. 

Anxiety and depression are usually treated with antidepressant drugs. However, these pharmaceuticals can cause side effects, such as headache, insomnia, agitation, sexual dysfunction, and drowsiness(41).

A small clinical trial showed that 79% of the participants who took CBD experienced a reduction in anxiety. This level remained decreased during the study duration(42).

Researchers have examined the experimental and clinical use of CBD. Multiple studies found that it showed antipsychotic and antiepileptic properties that might help reduce depression linked to stress(43).

In a 2011 study, participants with social anxiety received an oral dose of 400 milligrams (mg) of CBD or a placebo(44). Results showed that participants experienced a significant reduction of stress and anxiety levels after ingesting CBD. 

According to a 2015 study, CBD may help alleviate symptoms of anxiety for several conditions.  

These conditions include generalized anxiety disorder (GAD), panic disorder, social anxiety disorder (SAD), obsessive-compulsive disorder (OCD), and post-traumatic stress disorder (PTSD)(45).

A study published in 2018 also demonstrated CBD as a potential remedy to depression(46). 

The potential benefits of CBD oil may be linked to how CBD interacts with the brain. It was reported that CBD might affect how the brain reacts to serotonin that is present in the body(47).

Serotonin is a neurotransmitter that plays an essential role in mental health by regulating mood and social behavior(48). People who do not have enough serotonin may experience anxiety, while low serotonin levels may cause depression. 

A study also found that CBD helps maintain anandamide levels to reduce mood swings and emotional outbursts(49).

Anandamide, known as “the bliss molecule,” is responsible for stabilizing emotions, controlling feelings of happiness and euphoria. 

CBD vs. Sleep Problems

Numerous studies have suggested that CBD might help with sleep disorders, such as insomnia and its symptoms. 

People regularly use sleeping pills and prescribed medications to alleviate sleep disruptions, like insomnia. However, these treatments may have adverse effects and may take time to produce the desired outcome(50)

A study on CBD’s effects on the sleep-wake cycle of rats concluded that CBD increased the duration of the “deep sleep” phase(51).

Researchers found that CBD indirectly increases adenosine, a chemical responsible for signaling the brain to sleep and decreasing wakefulness(52).

In a case series published in The Permanente Journal, participants were given 25mg of CBD in capsule form each day. The researchers’ goal was to look into the effects of CBD on sleep and anxiety.

After the first month, 66.7% of the participants reported better sleep, and 79.2% experienced lower anxiety levels(53).

Recent clinical trials concluded that CBD might provide temporary insomnia relief(54). It may also act as a natural sleep aid without the side effects of over-the-counter drugs. 

While these studies highlight CBD’s potential in promoting quality sleep, more research is required on CBD’s long-term effects in regulating the sleep cycle in humans

CBD vs. Alzheimer’s Disease

Animal and test-tube studies have looked into the effects of CBD on Alzheimer’s disease. Studies have shown that CBD may help prevent the neurodegeneration associated with Alzheimer’s disease and may decrease inflammation(55)

People with Alzheimer’s may lose the ability to remember familiar people, places, or things. According to a 2014 rodent study, CBD might help retain one’s ability to recognize familiar faces(56)

Researchers of the long-term study also concluded that CBD helped prevent cognitive decline. Some scientists suggest that treatment with both CBD and THC may be more effective. 

A 2019 review found that CBD might help delay the onset and progress of Alzheimer’s disease(57). More research is being conducted to understand if there may be any clear benefits or the appropriate dosage required. 

Still, further human studies are needed to determine CBD’s effect on individuals with Alzheimer’s disease. 

CBD vs. Neurological Symptoms and Diseases

Research has suggested that CBD’s ability to interact with the endocannabinoid system and other brain signaling systems may benefit those with neurological disorders.

It was also found that CBD may help treat complications linked to epilepsy, including neuronal injury, neurodegeneration, and psychiatric diseases(58).

A 2012 study reported that CBD produced effects similar to those of certain antipsychotic drugs(59). According to the researchers, CBD compounds may provide a safe and effective treatment for people with schizophrenia.

Several studies have also shown that using CBD as a treatment improved sleep quality and overall quality of life for people with Parkinson’s disease(60).

Despite these promising results, research of CBD in the neurological area is relatively new and further studies are needed.  

CBD vs. Acne

Another promising use of CBD is acne treatment. Acne is a common skin condition caused by a number of factors, such as bacteria, genetics, inflammation, and the overproduction of sebum(61).

Sebum is an oily secretion made by sebaceous glands in the skin. Based on recent scientific studies, CBD’s anti-inflammatory properties may help lower the production of sebum(62)

A test-tube study found that CBD oil prevented the secretion of excessive sebum from sebaceous gland cells(63)

It was also found that CBD helped control the activation of pro-acne agents, such as inflammatory cytokines. Cytokines are small secreted proteins released by cells that regulate immunity and inflammation(64)

Research has suggested that applying CBD topically may also reduce inflammatory skin diseases, like psoriasis(65)

Due to its beneficial effects on acne, CBD is becoming a more commonly used ingredient in skin creams and ointments(66).

However, some experts have concerns about the lack of regulation for CBD-infused skin products. Further human studies are also needed to prove its effectiveness in treating acne. 

CBD for Cardiovascular Health

Recent studies have associated CBD with health benefits for the heart and circulatory system, including CBD’s properties to lower high blood pressure(67).

High blood pressure is linked to higher risks of health conditions, including heart attack, stroke, and metabolic syndrome. 

In a recent study, nine healthy men were treated with one dose of 600mg CBD oil. Researchers have found that a single dose of CBD reduced resting blood pressure(68)

The same study also gave the subjects stress tests that normally increase blood pressure. Based on the results, the subjects who took CBD had reduced blood pressure levels before and after the tests(69).

Studies have suggested that CBD’s stress- and anxiety-reducing properties are responsible for its potential to help with high blood pressure. 

Several animal studies have demonstrated CBD’s antioxidant and stress-reducing properties that may help reduce inflammation and cell death associated with heart disease. 

For instance, it was found that CBD treatment reduced oxidative stress and prevented heart damage in mice with heart disease(70). 

More studies are needed to determine any potential benefit of CBD for blood pressure or other heart conditions.

Researchers have found evidence that CBD may help reduce cancer-related symptoms and help prevent the spread of some types of cancer(71).

According to a 2012 review, CBD compounds might help suppress the growth of cancer cells and promote their destruction(72).

It was also found that CBD helped reduce side effects related to cancer treatment(73). The most common side effects of chemotherapy include nausea, vomiting, and pain.

In a study, CBD and THC were given to 177 individuals who were experiencing cancer-related pain but had not found relief from pain medications.

Those who received extracts containing both CBD and THC reported a significant reduction in pain, compared to those who were treated with THC only(74).

In another study, 16 people undergoing chemotherapy were given a 1:1 combination of CBD and THC administered via a mouth spray(75).

Findings showed that CBD and THC reduced chemotherapy-related vomiting and nausea better than standard treatment alone. 

A 2020 review discussed the addition of CBD to chemotherapy drugs. The review suggested that CBD may help improve the immune system’s response to cancer treatment(76).

Moreover, CBD has demonstrated anticancer and anti-tumor properties in test-tube and animal studies. The researchers believe that CBD may help the spread of breast, brain, prostate, colon, and lung cancer cells in animal subjects(77).

Researchers have also noted CBD’s lack of toxicity. However, more research is necessary to prove that CBD helps support standard cancer treatments. 

CBD vs. Symptoms of Drug Withdrawals 

Research supports the use of CBD in managing withdrawal symptoms. CBD has been shown to modify circuits in the brain related to substance abuse and drug addiction(78).

In a 2013 pilot study, smokers who used inhalers with CBD smoked fewer cigarettes than usual(79). 

It was also found that smokers stopped craving nicotine. This study suggested that CBD may help people quit smoking. 

A rat study reported that CBD helped reduce heroin-seeking behavior and morphine dependence(80).

According to a 2015 review, researchers found evidence that specific cannabinoids, such as CBD, might help reduce some symptoms associated with substance use disorders. These include pain, anxiety, insomnia, and other mood-related symptoms. 

The authors of the review noted that CBD might help people with opioid addiction disorders(81).

Additionally, a 2018 study concluded that CBD’s relaxing effects helped people reduce cravings during their withdrawal from tobacco(82).

Risks and Safety Considerations

According to the World Health Organization (WHO), CBD “is generally well-tolerated with a good safety profile(83).” However, like other medications, CBD may bring some risks.

Possible adverse effects of CBD include the following(84):

  • nausea
  • dry mouth
  • diarrhea
  • loss of appetite 
  • gastrointestinal problems 
  • liver damage
  • fatigue
  • drowsiness
  • changes in alertness
  • mood changes, like irritability

CBD may also interact with certain drugs or supplements, increasing the levels of these compounds in one’s blood. 

Consumers need to be wary of CBD’s interactions with other drugs and how these interactions could affect their medical conditions. CBD has a complex pharmacokinetic profile and should be treated like any other medication(85)

CBD is often marketed using unsubstantiated therapeutic claims. Some CBD oil products are also being sold as a supplement that can be used to help with several medical disorders.

However, the Food and Drug Administration (FDA) currently does not regulate the purity and safety of dietary supplements(86). Therefore, most CBD products in the market do not have approval from the FDA

Before buying any product, consumers should exercise caution and look for the product’s certificate of analysis (COA). The COAs help consumers know if the products are safe and effective to use. 

Still, before using CBD, one must first consult a doctor. Further research is still needed to prove CBD’s safety and effectiveness in treating various health conditions. 

For now, the FDA advises people not to depend solely on CBD as an alternative to conventional medical care(87)

CBD Legality 

In most parts of the United States, CBD is readily obtainable. Still, its exact legal status is complex. 

Although the federal government considers CBD in the same class as marijuana, it does not habitually enforce against it. 

In 2014, Congress granted state governments the legal right to grow, cultivate, and research industrial hemp through state-regulated agriculture departments and pilot programs(88)

Both hemp and marijuana come from the same Cannabis Sativa plant. The main distinguishing trait between the two is their THC levels. 

The 2014 federal Farm Bill also classified hemp and hemp-derived products with less than 0.3 percent THC separate from marijuana. 

The bill makes hemp-derived CBD products legal on the federal level, while marijuana-derived CBD products with higher THC concentrations are federally illegal. 

In December 2015, the Food and Drug Administration eased the regulatory requirements that allowed researchers to conduct CBD trials(89)

When the 2018 Farm Bill was passed, the growth, production, and manufacturing of hemp became legalized on the federal level. This law allowed hemp-derived products, such as CBD oil, to become more easily available in the market. 

All 50 states also have laws that legalize CBD with varying degrees of restriction(90). When traveling, people should check the state laws of their destination. 

Under some state laws, CBD products derived from hemp are still illegal. Meanwhile, marijuana-derived CBD products are legal in some states.

Congress’ most recent ruling in 2018 removed industrial hemp as a Schedule I drug from the federal Controlled Substance List(91). This law allows for a hemp market and sales across state borders with proper commercial licensing. 


CBD oil contains cannabidiol, which is a non-psychoactive compound extracted from hemp plants. Due to its potential anti-inflammatory and neuroprotective properties, CBD is commonly used in health and wellness products. 

Although it is closely related to the marijuana plant, CBD does not produce the same mind-altering effects. It makes the compound an appealing option for those who seek alternative treatment to various medical conditions

Some of CBD’s potential health benefits include epilepsy treatment, pain management, anxiety relief, neuroprotection, and alleviating cancer-related symptoms. Studies also suggested that CBD helps reduce acne and enhance cardiovascular health. 

There are three types of CBD: full-spectrum, broad-spectrum, and CBD isolates.

Full-spectrum CBD contains all the naturally occurring cannabinoids in the cannabis plant. Its low levels of THC (less than 0.3 percent) are not enough to cause a “high” sensation. 

Studies have also pointed out that the cannabinoids and terpenes in a full-spectrum produce an “entourage effect.” This effect is found to have greater medicinal properties than CBD isolates

Broad-spectrum CBD contains multiple cannabinoids in the hemp plant, except for THC. Meanwhile, CBD isolate is the purest form of cannabidiol and does not contain other chemical compounds

CBD products may be taken through various methods: sublingual, ingestion, inhalation, and topical. Each method has different bioavailability that may influence CBD’s effect on the body.

CBD dosage also depends on several factors, such as body weight, metabolic rate, genetics, and product’s frequency of use. It is best to consult a medical professional to determine the appropriate dosage. CBD may not be appropriate for everyone and there may be other safe, established first-line treatment options. 

Despite its promising effects and overall safety profile, CBD entails some risks. Possible side effects include nausea, vomiting, fatigue, and potential drug interactions. The long-term effects of CBD or other cannabinoids are yet unknown for general or special populations.

The FDA currently has one approved CBD product for epilepsy, Epidiolex. Due to the lack of regulation, the FDA advises to be wary of most CBD products without approved therapeutic claims. 

Most hemp-derived CBD products, however, are legal on the federal level. The Farm Bill of 2018 allows the cultivation, production, and distribution of hemp products. 

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