CBD Guide: Everything you need to know

New to CBD? We demystify the terminology and explain the effects, benefits, and safety of CBD. Learn all about the types of CBD and CBD products and how they differ.

Last updated: Dec 29th, 2023
CBD Guide

Cannabidiol (CBD) is making waves as a leading trend in health and wellness. This cannabis-derived compound doesn’t get you high and has been touted to relieve anxiety, pain, insomnia, and other common health problems.

You can find it in everything from oil to infused beverages. But what is CBD exactly? How does it differ from THC and marijuana? Is there any evidence that it works?

In this CBD guide, we’ll answer these and other questions to dispel the myths and misconceptions about this popular natural remedy.

Jump to

Jump to:

What are cannabinoids?

Cannabinoids are natural compounds that can interact with your body’s endocannabinoid system (ECS). There are three types of cannabinoids:

  1. Endocannabinoids: made by our bodies, like anandamide
  2. Phytocannabinoids: from plants, like CBD and THC
  3. Synthetic cannabinoids: made in a lab, like dronabinol

Most people are familiar with tetrahydrocannabinol (THC), the cannabinoid that gets you high when smoking or vaping marijuana or consuming marijuana edibles. THC is usually the most abundant cannabinoid found in cannabis.

What is CBD?

CBD is a phytocannabinoid but, unlike THC, is completely non-intoxicating.

CBD has a long list of potential health benefits, including relief of anxiety, pain, inflammation, and much more. That’s why millions of people use CBD products to support their health.

CBD is found in all types of cannabis but is usually derived from hemp, a variety with high CBD levels and less than 0.3% THC. Hemp is legal in many countries, whereas cannabis, also known as marijuana, is more restricted because of its intoxicating effects.

How cannabinoids affect us

By definition, all cannabinoids can interact with your body’s endocannabinoid system (ECS). Discovered in the 1990s, this system consists of endocannabinoids, the cannabinoid receptors they activate, and enzymes that build and break them down.

Research suggests that the ECS regulates vital processes, including:

  • Cognitive function
  • Cardiovascular function
  • Pain
  • Immunity
  • Inflammation
  • Metabolism

This regulation helps maintain homeostasis: a healthy state of internal balance.

We’re still learning how critical the ECS is to our health. For example, growing evidence suggests that some difficult-to-treat conditions – including migraines, fibromyalgia, and irritable bowel syndrome (IBS) – are caused by a deficient endocannabinoid system.

CBD and the ECS

CBD is somewhat different from most cannabinoids because it doesn’t have a strong attraction to the two main cannabinoid receptors: CB1 and CB2. Instead, it may act as an allosteric modulator of these receptors, changing their function.

More importantly, research suggests that CBD can influence the ECS differently: by inhibiting the enzyme fatty acid amide hydrolase (FAAH). This enzyme breaks down anandamide, one of the two primary endocannabinoids made by our bodies. In doing so, CBD can increase anandamide levels.

CBD also interacts with dozens of other receptors, enzymes, and proteins. So far, researchers have uncovered about 76 distinct molecules affected by CBD, which may explain its impressive range of beneficial effects.

Types of CBD

There are three kinds of CBD: isolate, full-spectrum, and broad-spectrum. You’re likely to see one of these terms on the label of a CBD product. It’s essential to understand the differences between the three to choose the right one for your needs.


As the name suggests, isolate is pure CBD without anything else. This type of CBD is considered less effective than other forms because it lacks dozens of cannabinoids, terpenes, and other beneficial compounds found in hemp.

The main advantage of CBD isolate is that it’s completely free of THC and can sometimes be cheaper than broad- and full-spectrum products. Broad-spectrum formulas better suit people looking for THC-free CBD.


Full-spectrum CBD products are the best option for most people unless you need to steer clear of THC. This type of CBD provides a range of hemp compounds, including:

  • CBD
  • THC (less than 0.3%)
  • Minor phytocannabinoids like CBN, CBG, and CBC
  • Terpenes
  • Flavonoids

These natural substances have beneficial effects of their own and work synergistically with CBD, producing what researchers call the “entourage effect.” Thanks to this effect, whole-plant cannabis products appear to be more potent and cause fewer side effects than isolated cannabinoids like CBD or THC.


Broad-spectrum CBD contains the same wide range of beneficial hemp compounds as full-spectrum but without THC. It’s slightly less effective but still superior to CBD isolate.

Broad-spectrum products are ideal for people who need to avoid THC altogether, such as those who get drug tested for work, are extremely sensitive to THC, or live in states where THC-containing CBD products are illegal.

But there is one caveat: broad-spectrum products can still contain trace, undetectable amounts of THC. Albeit unlikely, it’s theoretically possible to consume enough THC to show up on a drug test if you regularly use a broad-spectrum CBD product, especially if it’s of low quality.

Ways to take CBD

You have four main options for consuming CBD:

  1. Sublingual: putting CBD under your tongue, allowing it to absorb directly into blood vessels and bypass the digestive tract. Made popular by CBD oil, this consumption method combines efficient absorption with relatively fast and long-lasting effects, making it what most consider the best method.
  2. Oral: Ingesting CBD as edibles, capsules, or pure isolate. This administration route is the most convenient but also the least effective. Out of all the CBD consumption methods, it has the lowest bioavailability – how much of a drug you actually absorb. Oral CBD has an estimated bioavailability of about 6-24%, which means you’re only absorbing that small percentage of the original amount you took. It also takes the longest to start working, taking about 30 minutes on an empty stomach but up to two hours depending on how much you ate.
  3. Inhalation: Absorbing CBD through the lungs by smoking hemp flower or vaping CBD e-liquid. This method boasts the highest potential bioavailability (~60%) and fastest effects of any consumption method, kicking in almost immediately. But inhaling CBD has two downsides: shorter-lasting effects (1-4 hours) and potential health risks, such as reduced cardiorespiratory function and ingesting toxic compounds like formaldehyde.
  4. Topical: Putting CBD directly on your skin in the form of a cream or another topical product. This route is ideal for localized relief of muscle or joint pain because the CBD will only affect the area it’s applied to. There are also transdermal CBD products like patches, penetrating the skin and reaching the bloodstream. Topical products are popular with athletes and people with arthritis and other painful conditions.
MethodAbsorption/ BioavailabilityTime to Feel EffectsAverage DurationProducts
SublingualMedium15-40 min4-6 hoursCBD oil, spray, isolate
OralLow30-120 min6+ hoursCBD capsules, edibles, beverages, isolate
InhalationMedium-highWithin a minute1-4 hoursCBD vape oil, hemp flower
TopicalMedium10-60 min2+ hoursCBD cream, body oil, patch

Types of CBD products

CBD comes in a wide variety of product forms. Here’s a quick look at the most common options, ranked from most to least popular.

CBD oil

CBD extract dissolved in a carrier oil like MCT oil, which is applied under the tongue. CBD oil is popular because it’s absorbed well, has long-lasting effects, is cost-effective, and makes it easy to control dosage.

CBD gummies

Delicious CBD-infused edibles that provide precise doses. CBD gummies are easy to use, discreet, and convenient but suffer from low absorption.

CBD capsules

Most CBD capsules are softgels that contain a precise dose of CBD oil, although some products contain pure CBD isolate powder. They have similar advantages to gummies but also suffer from poor absorption.

CBD topicals

Creams, balms, body oils, and other products that you apply to the skin. Topicals are ideal for localized pain relief and skin issues.

CBD vapes

CBD-infused vape e-liquids, disposable vape pens, and vape cartridges, which typically combine CBD with standard vape ingredients like vegetable glycerin (VG) and propylene glycol (PG) and flavoring. Vaping is preferred when you need immediate relief.

CBD beverages

CBD-infused tea, coffee, sodas, and other dry or liquid drinks. These products are similar to gummies and other edibles but tend to be gimmicky because most contain small doses of CBD.

CBD concentrates

Typically consumed by vaping or dabbing, concentrates contain high levels of CBD and potentially terpenes. Common examples include CBD isolate, shatter, crumble, and wax.

CBD hemp flower

Smokable hemp flower that can be rolled into a joint or used in a dry herb vaporizer or bong/pipe, similar to regular cannabis.

CBD bath bombs

CBD-infused bath bombs that dissolve in water and work best for soothing muscles and supporting skin health. Their effectiveness remains contested until more studies are done.

CBD paste

Paste is similar to full-spectrum CBD oil but is thicker because it’s less processed and contains plant waxes. If you’re looking for a product as close to natural as possible, this is it.

CBD patches

Transdermal patches allow CBD to absorb through the skin into the blood vessels and should be a good option for localized pain. More research is needed to prove their effectiveness.

CBD dosage

There’s no one-size-fits-all dosage for CBD. It varies depending on your body weight, genetics, gender, the severity of your issues, the type of product you’re using, and other factors. That’s why health experts recommend the “start low and go slow” approach.

  1. Begin with a 10-15 mg dose of CBD or the amount recommended by your CBD product and wait for two hours to see how it affects you.
  2. If you don’t notice any changes, raise the dose and try again.
  3. Repeat this method until you settle on the CBD amount that provides you with the desired effects.

As a general rule of thumb, most people take 20-100 mg of CBD daily in one or two doses, although some individuals with severe conditions may use larger amounts.

How CBD products are made

All CBD products start out as hemp. After the plants are harvested, they’re extracted to isolate the CBD and other beneficial compounds. Extraction seeks to separate the trichomes – hair-like structures containing cannabinoids and terpenes – which are most abundant on hemp flowers.

The two most common CBD extraction methods are ethanol (alcohol) extraction and carbon dioxide extraction.

Ethanol (alcohol) extraction

Ethanol has been used to make botanical tinctures for thousands of years, and CBD extraction continues that rich tradition.

Ethanol’s safety, availability, and ease of use make it an excellent choice for both small and large-scale CBD extraction. It also holds the distinction of dissolving both fat and water-soluble compounds.

Carbon dioxide extraction

Carbon dioxide (CO2) extraction is a relative newcomer to the world of cannabis. It uses pressure and heat to turn carbon dioxide supercritical, a state where it behaves both as a gas and liquid.

CO2 extraction is more expensive than other methods but is highly tunable, which means it can be modified to extract specific compounds. It’s also considered cleaner and more environmentally friendly because it doesn’t leave behind any residual solvents and is non-toxic, renewable, and non-flammable.

Whichever method is used, the resulting full-spectrum CBD extract undergoes further processing depending on the desired end product. For example, to make a broad-spectrum CBD oil, the extract is winterized to remove unwanted lipids and waxes, refined to remove THC, and blended with MCT oil or another carrier oil.

CBD third-party testing

The CBD industry is unregulated and full of low-quality products. Although things have improved in the past few years, it’s still common to find products that contain less CBD than advertised, the wrong type of CBD extract, or contaminants like pesticides or residual solvents.

That’s why reputable CBD companies send samples of their products for testing at independent, accredited laboratories. The lab technicians can do two types of tests:

  1. Potency: checking the levels of CBD, other cannabinoids, and potentially terpenes.
  2. Contaminants: checking for pesticides, heavy metals, residual solvents, mold, and other potential contaminants.

The test results are recorded in a Certificate of Analysis (CoA) document, which is sent back to the CBD company. You should only buy products from brands that publicly post their third-party CoAs.

If possible, you should also look at the CoAs yourself to make sure they match the label in terms of cannabinoid content and CBD type.

Benefits of CBD

CBD has a wide range of potential health benefits. It’s been examined in over 9000 studies, highlighting anti-inflammatory, anxiolytic (anti-anxiety), antidepressant, analgesic (pain-relieving), neuroprotective, antiepileptic, antiemetic (anti-nausea), antiviral, antibacterial, anti-cancer, and anti-addictive properties that may help with:

  • Epilepsy disorders, particularly Lennox Gastaut syndrome (LGS), Dravet syndrome (DS), and tuberous sclerosis complex (TSC)
  • Anxiety disorders, including generalized anxiety disorder, social anxiety disorder, and post-traumatic stress disorder
  • Depression, psychosis, autism, and ADHD
  • Insomnia and other sleeping problems
  • Chronic pain caused by arthritis, cancer, diabetic neuropathy, multiple sclerosis, and other issues
  • Inflammation, which is a central feature of many common chronic conditions
  • Neurodegenerative disorders such as Alzheimer’s and Parkison’s disease
  • Addiction to opioids, nicotine, and other drugs, with potential to help the opioid epidemic
  • Digestive disorders such as ulcerative colitis
  • Various types of cancer
  • Diabetes and its complications
  • Skin conditions such as acne, psoriasis, and eczema
  • Sports performance and recovery

However, the strength of the evidence varies between health conditions. Some, like rare types of treatment-resistant epilepsy, are backed by high-quality clinical trials, prompting the FDA to approve the CBD-based drug Epidiolex for these uses.

Others have only been examined in a handful of human studies or only petri dish and animal research, so the level of evidence is weaker.

But that hasn’t stopped people from using CBD to treat their symptoms. According to a 2018 study of 2409 CBD users, 62% took CBD to treat a medical condition. The four most common conditions were chronic pain, anxiety, depression, insomnia, and other sleep disorders.

CBD safety and side effects

It’s best to talk to your doctor before starting CBD, especially if you take prescription medications or have underlying conditions such as hypotension. High doses of CBD may interact with some medications because it can affect the liver enzymes that help the body metabolize various drugs. If you’re pregnant, avoid taking CBD until we know more about its safety during pregnancy. According to numerous studies, CBD is a relatively safe compound for most people. A 2018 report by the World Health Organization also concluded that “CBD is generally well tolerated with a good safety profile.”

CBD is not addictive or intoxicating. Its potential side effects are mild and include:

  • Tiredness and sleepiness
  • Diarrhea and nausea
  • Dry mouth
  • Low blood pressure
  • Lightheadedness
  • Changes in appetite or weight

Still, your likelihood of experiencing side effects is low. They have only been reported in studies using high oral uses of pure CBD, which doesn’t really translate to real-world CBD use. Few people consume pure CBD, instead opting for sublingual CBD oils and full-spectrum formulations, which are even less likely to cause side effects.

Recent CBD research

There’s a perpetual stream of new studies looking at CBD. One of the most relevant recent developments is the slew of data showing that CBD and other cannabinoids may help with COVID-19.

The most important study, published in February 2022, reported that cannabidiolic acid (CBDa), the parent molecule of CBD, may help prevent coronavirus infections.

The researchers found that CBDa and another precursor cannabinoid called CBGa blocked the coronavirus spike protein from entering human cells. They concluded: “Orally bioavailable and with a long history of safe human use, these cannabinoids, isolated or in hemp extracts, have the potential to prevent as well as treat infection by SARS-CoV-2.”

In January, a similar study found that CBD inhibits COVID virus infections in mice and human cells.

The study also discussed data from the National COVID Cohort Collaborative project showing that people taking CBD were less likely to test positive for Covid than those who weren’t.

CBD legality

Hemp-derived CBD products became federally legal when Congress passed the 2018 Farm Bill. The bill defines hemp as cannabis containing 0.3% or less delta-9 THC, making it a legal agricultural commodity.

Each U.S. state also has the authority to regulate hemp and CBD in its own way, with most choosing to follow the federal model. One of the only notable exceptions is Kansas, which only allows CBD products with 0% THC.

CBD for pets

Most animals, including dogs and cats, have an endocannabinoid system. While it’s not 100% identical to ours, this does suggest that CBD can be beneficial for pets in many of the same ways as humans.

CBD is most commonly used to relieve anxiety, arthritis pain, inflammation, cancer, and other issues in dogs, cats, and other pets. That’s why many companies sell CBD products marketed specifically for your furry friend.

Although the research evidence for CBD’s benefits in dogs, cats, and other pets is lacking, there are some encouraging findings:

  • In a 2018 study, CBD improved comfort and activity in dogs with osteoarthritis.
  • In a similar 2020 study, high-dose CBD outperformed placebo on quality of life scores in dogs with osteoarthritis.
  • In a 2019 study, CBD outperformed placebo in improving seizures in dogs with difficult-to-treat epilepsy.
  • In a 2021 study, CBD showed anti-inflammatory and immuno-modulating effects in dog immune cells.
  • In a 2020 petri dish study, CBD showed anti-cancer effects against canine cancer; similar results were reported by a 2021 study of bladder cancer.
  • In a 2021 study of stalled horses, CBD reduced aggression and other negative behaviors.

Early research also suggests that CBD products are safe in healthy dogs and cats. However, more studies are needed because pets can be more sensitive to cannabinoids than humans.

In particular, dogs are known to have more brain cannabinoid receptors, which makes them more susceptible to THC intoxication and related side effects such as vocalization, drooling, and lack of coordination.

If you plan to use full-spectrum CBD products for your pet, be sure to start with low doses and pay close attention to how they react.




Innerbody uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

  1. Phytocannabinoids and endocannabinoids

  2. Cannabidiol: State of the art and new challenges for therapeutic applications

  3. Review of the Endocannabinoid System

  4. The Endocannabinoid System and Cannabidiol: Past, Present, and Prospective for Cardiovascular Diseases

  5. Clinical Endocannabinoid Deficiency Reconsidered: Current Research Supports the Theory in Migraine, Fibromyalgia, Irritable Bowel, and Other Treatment-Resistant Syndromes

  6. Cannabidiol for Pain Treatment: Focus on Pharmacology and Mechanism of Action

  7. Diversity of molecular targets and signaling pathways for CBD

  8. Cannabidiol primer for healthcare professionals

  9. Potential Clinical Benefits of CBD-Rich Cannabis Extracts Over Purified CBD in Treatment-Resistant Epilepsy: Observational Data Meta-analysis

  10. Towards Better Deliver of Cannabidiol (CBD)

  11. A phase I trial of the safety, tolerability and pharmacokinetics of cannabidiol administered as single-dose oil solution and single and multiple doses of a sublingual wafer in healthy volunteers

  12. Critical Aspects Affecting Cannabidiol Oral Bioavailability and Metabolic Elimination, and Related Clinical Implications

  13. Cannabinoid Delivery Systems for Pain and Inflammation Treatment

  14. The Impact of Vaping Cannabidiol A Case Series of Young Adults

  15. Public Health Consequences of E-Cigarettes

  16. The pharmacokinetics and the pharmacodynamics of cannabinoids

  17. Processing and extraction methods of medicinal cannabis: a narrative review

  18. Clinicians' Guide to Cannabidiol and Hemp Oils

  19. FDA Approves New Indication for Drug Containing an Active Ingredient Derived from Cannabis to Treat Seizures in Rare Genetic Disease

  20. Use of cannabidiol in anxiety and anxiety-related disorders

  21. Cannabidiol: A Potential New Alternative for the Treatment of Anxiety, Depression, and Psychotic Disorders

  22. The therapeutic role of Cannabidiol in mental health: a systematic review

  23. Use of cannabidiol (CBD) for the treatment of chronic pain

  24. From Cannabis sativa to Cannabidiol: Promising Therapeutic Candidate for the Treatment of Neurodegenerative Diseases

  25. Cannabidiol: Swinging the Marijuana Pendulum From ‘Weed’ to Medication to Treat the Opioid Epidemic

  26. Cannabidiol and substance use disorder: Dream or reality

  27. Cannabidiol and Other Non-Psychoactive Cannabinoids for Prevention and Treatment of Gastrointestinal Disorders: Useful Nutraceuticals?

  28. Cannabidiol (CBD) as a Promising Anti-Cancer Drug

  29. Role of the endocannabinoid system in diabetes and diabetic complications

  30. Therapeutic Potential of Cannabidiol (CBD) for Skin Health and Disorders

  31. Cannabidiol and Sports Performance: a Narrative Review of Relevant Evidence and Recommendations for Future Research

  32. A Cross-Sectional Study of Cannabidiol Users

  33. Cannabidiol Interactions with Medications, Illicit Substances, and Alcohol: a Comprehensive Review

  34. Considerations and Implications of Cannabidiol Use During Pregnancy

  35. Dosage, Efficacy and Safety of Cannabidiol Administration in Adults: A Systematic Review of Human Trials

  36. Cannabidiol (CBD) Critical Review Report

  37. Cannabinoids Block Cellular Entry of SARS-CoV-2 and the Emerging Variants

  38. Cannabidiol inhibits SARS-CoV-2 replication through induction of the host ER stress and innate immune responses

  39. The Farm Bill, hemp legalization and the status of CBD: An explainer

  40. The Endocannabinoid System of Animals

  41. A randomized, double-blind, placebo-controlled study of daily cannabidiol for the treatment of canine osteoarthritis pain

  42. Pharmacokinetics, Safety, and Clinical Efficacy of Cannabidiol Treatment in Osteoarthritic Dogs

  43. Randomized blinded controlled clinical trial to assess the effect of oral cannabidiol administration in addition to conventional antiepileptic treatment on seizure frequency in dogs with intractable idiopathic epilepsy

  44. Effect of Cannabidiol (CBD) on Canine Inflammatory Response: An Ex Vivo Study on LPS Stimulated Whole Blood

  45. The effect of cannabidiol on canine neoplastic cell proliferation and mitogen-activated protein kinase activation during autophagy and apoptosis

  46. Combination therapy with cannabidiol and chemotherapeutics in canine urothelial carcinoma cells

  47. The Effects of Feeding Cannabidiol Oil on Behavior of Stalled Horses

  48. Single-Dose Pharmacokinetics and Preliminary Safety Assessment with Use of CBD-Rich Hemp Nutraceutical in Healthy Dogs and Cats

  49. Toxicology of Marijuana, Synthetic Cannabinoids, and Cannabidiol in Dogs and Cats

  50. Does Cannabidiol Protect Against Adverse Psychological Effects of THC?

  51. Reasons for cannabidiol use: a cross-sectional study of CBD users, focusing on self-perceived stress, anxiety, and sleep problems

  52. A Systematic Review on the Pharmacokinetics of Cannabidiol in Humans

  53. Smoking, Vaping, Eating: Is Legalization Impacting the Way People Use Cannabis?

  54. Safety and side effects of cannabidiol, a Cannabis sativa constituent

  55. Taming THC: potential cannabis synergy and phytocannabinoid-terpenoid entourage effects