What is Cannabidiol (CBD) | Guide | CBDnerds 2021

What is CBD? How does it work? Here’s a beginner’s guide explaining the key things you need to know about this popular natural supplement.

Gleb Oleinik Updated on October 14, 2021

Introductory Guide to CBD

You’ve probably heard of CBD oil. This non-intoxicating cannabis product is quickly becoming the leading trend in natural health and wellness.

CBD is changing the conversation surrounding cannabis and its health benefits and applications.

It’s used by millions of people around the world to treat a wide range of common ailments, including anxiety, pain, and insomnia. It can also be taken for certain serious conditions that don’t respond well to standard treatments and other medications.

There’s much to learn about CBD oil benefits, including its effects, legality, and safety. In this beginner’s guide, we’ll answer common CBD questions and discuss the key facts you need to know to make the best use of this beneficial natural compound.

What is CBD?

CBD stands for cannabidiol, which is a compound found in cannabis. It belongs to a class of natural chemicals called cannabinoids, which are largely responsible for the health effects of the cannabis plant.

Most of us are familiar with tetrahydrocannabinol (THC) — the cannabinoid largely responsible for the intoxicating effects of cannabis. But unlike THC, CBD is non-psychotropic, meaning it can’t get you high.

But CBD and THC are not alone. So far, researchers have identified over 120 cannabinoids in cannabis. ¹ Most of them are considered “minor” because they’re present in small concentrations, such as cannabinol (CBN), cannabigerol (CBG), and cannabidivarin (CBV).

These minor cannabinoids also have effects of their own, some of which are similar to CBD, whereas others are unique.

Most people take CBD in the form of CBD oil. This liquid supplement can contain either pure CBD or a CBD-rich hemp extract derived from whole plants dissolved in a plant-based oil such as MCT oil.

However, you can also take CBD in many other product forms, including capsules, soft gels, gummies, vaping products, drinks, and topicals.

What is CBD

Is CBD Legal?

There are two main types of cannabis:

  • Marijuana — the regular, THC-rich cannabis that can make you high
  • Hemp — a non-intoxicating variety of cannabis with high CBD and low THC (<0.3%) levels


In the United States, CBD derived from hemp became legal with the passing of the 2018 Farm Bill. It should be noted that even though CBD is legal, the Food & Drug Administration (FDA) hasn’t approved cannabidiol as a medically-applicable substance, with the exception of Epidiolex.

Meanwhile, Canada fully legalized all cannabis in 2018, making CBD legal by extension.

The legal status of CBD in other countries vary and is largely dependent on how cannabis is regulated. For example, most countries that ban CBD do not recognize the difference between marijuana and hemp and regulate them as one and the same.

Generally speaking, CBD’s legality falls into one of four categories: completely banned, restricted (medical use with a doctor’s prescription), legal grey area (no clear laws), or fully legal.

Here’s a quick breakdown by continent:

  • Central America — banned in most countries
  • South America — restricted to medical use or banned in most countries
  • Europe —legal or in a legal grey area in most countries
  • Africa — banned in all countries except South Africa
  • Asia — banned in Middle Eastern nations but varies from legal to banned in other Asian countries
  • Australia and New Zealand — restricted to medical use, although this may soon change

How Does CBD Work?

Like other cannabinoids, CBD primarily works by interacting with the body’s endocannabinoid system (ECS), which controls a range of physiological, cognitive, and immune processes.

Discovered fairly recently, this essential system has three parts: ²

  • Endocannabinoids which are naturally made by your body
  • Enzymes that make and break down endocannabinoids
  • Cannabinoid receptors found throughout the body, but especially abundant in the brain (CB1 receptor) and immune system tissues (CB2 receptor)


You can think of these receptors as locks and cannabinoids as the keys that open them, producing different health effects in the process.

Cannabinoid receptors can respond to both endocannabinoids (cannabinoids naturally made in the body) and phytocannabinoids (plant-derived cannabinoids from cannabis).

THC and CBD are both phytocannabinoids but they interact with the body’s cannabinoid receptors differently.

THC produces the characteristic cannabis high by binding to the CB1 receptor. But CBD is a little different. Instead of binding to cannabinoid receptors directly, it can change the function of CB1. ³ In addition, CBD can counteract the enzyme that normally breaks down your endocannabinoids, prolonging their effects. ⁴

The ECS has an immense impact on your health. It regulates everything from brain function to metabolism to help your body maintain an internal state of balance.

There’s even mounting evidence that abnormal ECS function — a theory called clinical endocannabinoid deficiency — may play a role in difficult-to-treat disorders such as migraines and fibromyalgia. ⁵

CBD oil effects go beyond its influence on the ECS. These include interactions with other receptors that regulate pain, inflammation, mood, anxiety, and many other processes. ⁶ ⁷

This is why CBD seems to have so many potentially beneficial effects.

What is the Endocannabinoid System

The Different Types of CBD

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

Full-spectrum CBD is a whole-plant extract containing all the cannabinoids and other active compounds found in hemp.

Broad-spectrum CBD is identical to full-spectrum but with except for one major difference — the removal of THC.

Isolate is pure CBD with THC and all other active compounds removed, which looks like an odorless white powder.

Full-spectrum CBD is believed to be the most effective form of CBD because of something scientists call the “entourage effect.” ⁸

First proposed by Israeli researchers in 1998, this evidence-based theory suggests that cannabinoids and other compounds in cannabis work together in synergy. ⁹ Put simply, the entourage effect means that cannabis seems to work best as a whole-plant preparation — with CBD, minor cannabinoids, and other active compounds together.

To illustrate this, think of an orchestra. As a musical ensemble, an orchestra will sound far more impressive and grand than a piano or violin on its own.

Similarly, using all the chemical components of cannabis together can produce greater effects than CBD or any other cannabinoid on its own.

CBD isolate does not benefit from the entourage effect. That’s why it’s considered less effective than full and broad-spectrum extracts, requiring larger doses and which comes with a higher likelihood of producing side effects. ¹⁰

There’s one other major player in the entourage effect that’s missing from CBD isolate: terpenes.


Terpenes are a diverse group of aromatic compounds found in plants. They’re responsible for the unique aromas and scents of various plants, including different strains of cannabis.


More importantly, terpenes contribute to the entourage effect through their unique health properties and synergistic interactions with cannabinoids. ¹¹


CBD Oil Effects & Safety

Many people are curious about how CBD makes you feel. But because it’s non-intoxicating, CBD oil effects are usually quite subtle; it’s more about what you stop feeling when you take CBD. For instance, CBD can relieve anxiety, making you feel more calm and relaxed.

CBD can also cause minor side effects. These include tiredness, drowsiness, diarrhea, dry mouth, low blood pressure, lightheadedness, and changes in appetite or weight. ¹²

Similar to grapefruit, CBD can also interfere with how your liver breaks down many prescription drugs, increasing or lowering their effects. ¹³

However, these side effects have only been reported in studies using very high daily dosages, so most people don’t need to worry about them. Human studies suggest that doses even up to 1,500 mg per day remain well-tolerated.

On the whole, research has shown that CBD is an exceptionally safe compound with no addictive properties. In fact, some studies suggest that it may help with addiction to opioids and other substances. ¹⁴

It also doesn’t seem to produce tolerance or withdrawal effects when taken over long periods of time. Most of the safety concerns around CBD products are not related to CBD itself.

For example, a minority of people who are highly sensitive to THC might experience increased anxiety and other unwanted effects from the residual amount of THC still present in full-spectrum CBD products (<0.3%).

In other words, these susceptible individuals can still get a little “high” from full-spectrum CBD oil even though it’s largely devoid THC.

However, unlike using CBD oils and other ingestible forms, vaporizing CBD comes with the general risks of vaping, such as inhaling potentially toxic compounds that may contribute to a higher risk of cardiovascular and lung issues. ¹⁵

CBD Dosage

There are no official CBD dosage recommendations and the optimal dose varies from person to person.

It depends on numerous factors that include your body weight, genetics, the specific symptoms you’re looking to address, and their severity. On top of that, the type, concentration, and delivery method of your CBD product also matter.

For example, products that contain CBD isolate are weaker than those made with full-spectrum CBD. Similarly, capsules and other oral CBD products have poor absorption, so their effects will not be as strong as CBD oil tinctures or vape e-liquids.

The bottom line is that a dose that might work well for one person could be entirely insufficient for someone else. Having said that, on average, most people take between 20–50 mg doses of CBD oil once or twice daily.

CBD Dose

Overall, the most recommended approach to figuring out the right amount of CBD for you is to start with a small amount (10–15 mg) and go up from there.


If you don’t notice any effect, you can gradually increase the dosage over time until you settle on the amount that provides the desired effects.


You can also follow the dosage instructions of your particular CBD product, or use them as a starting point for the above method.


Taking high doses of CBD (200 mg and higher) increases your likelihood of side effects. Having said that, it’s difficult to take too much.

According to research studies, even daily doses of 1,500 mg are tolerated well. ¹⁶

CBD Oil Benefits & Health Conditions

CBD has a wide range of potential health benefits. Research studies have highlighted the following therapeutic properties:

  • Anti-inflammatory
  • Antioxidant
  • Antiemetic (nausea-relieving)
  • Anxiolytic (anxiety-reducing)
  • Antidepressant
  • Analgesic (pain-relieving)
  • Neuroprotective (protects neurons from damage)
  • Anticonvulsant
  • Antipsychotic
  • Antitumor and anti-proliferative
  • Chronic pain
  • Cardioprotective
  • Antibacterial
  • Antiviral
  • Immunomodulatory (promoting or suppressing some elements of immune function)


Thanks to these and other beneficial qualities, CBD is used for a vast array of health problems, including mental, sleep, digestive, neurodegenerative, cardiovascular, skin, inflammatory, autoimmune, metabolic, and addiction disorders.

There’s also early evidence that CBD may have anti-cancer effects. ¹⁷

CBD oil benefits can range from providing symptom relief to directly addressing the causes of a health condition.

Meanwhile, specific conditions where CBD has shown promise in medical research on human and animal models include:

  • Social anxiety disorder (SAD) ¹⁸
  • Post-traumatic stress disorder (PTSD) ¹⁹
  • Depression ²⁰
  • Alzheimer’s and Parkinson’s disease ²¹ ²²
  • Arthritis ²³
  • Type 1 diabetes and diabetic complications such as retinopathy ²⁴ ²⁵
  • Stroke
  • Lennox-Gastaut syndrome, Dravet syndrome, and other types of epilepsy ²⁶
  • Schizophrenia ²⁷
  • Inflammatory bowel disease (IBD) ²⁸
  • Acne ²⁹
  • Psoriasis and eczema ³⁰
  • Atherosclerosis ³¹


However, much of the current evidence is restricted to test tube and animal studies. At this time, the only health condition for which there is substantial enough evidence to support CBD use is in certain types of treatment-resistant epilepsy.

For most other conditions, more human research is needed before we have conclusive evidence for CBD oil benefits.

CBD Health


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Gleb Oleinik

Gleb Oleinik is a freelance CBD & cannabis writer from Vancouver, Canada. He’s read thousands of studies about cannabinoids and other beneficial natural compounds, helping him translate complex science into plain language. He’s also written third-party lab test reports of CBD products and knows the industry inside and out. When he’s not writing, Gleb likes to spend his time in the gym and out in nature.

Frequently Asked Questions

Most people use CBD for everyday issues such as anxiety, pain, and difficulty sleeping. However, it can have a positive effect on many other types of health disorders.