CBD bioavailability: What is it and why should I care?

CBD Bioavailability: What is it and why should I care?


  • Bioavailability refers to the amount of an administered substance reaching the bloodstream.
  • The higher the bioavailability, the less of the active ingredient is needed to experience the effects.
  • Different CBD products have different bioavailability.
  • Understanding the bioavailability of CBD can help users find the optimal CBD dosage.
  • Learning how to increase CBD bioavailability allows for more efficient use of CBD. 

Our bodies are constantly working – repairing, monitoring, adjusting, and defending, no matter what we do. And while we cannot consciously influence any of these functions, we can support our bodies by living a lifestyle that contributes to our inner systems working well and efficiently.

More and more people decide to use CBD to do just that. And it's not a surprise. With an increasing number of people struggling with the pressure of modern life, CBD seems to be the perfect addition to any wellness routine.

When venturing into the world of CBD for the very first time, many people are surprised to learn that there is more to it than just CBD oils.

With so many variations of CBD products available on the market, it might feel a bit overwhelming to choose the right one for you.

Checking the product description on the box is usually not enough.

Producers tend to focus on the application technique and the possible effects. Yet, they often forget to explain how the form of application (whether it is an oil, a spray, a topical, etc.) can have an impact on the amount of CBD your body will end up utilising. And that's what we will talk about today.

Let's bring our focus to this crucial yet often marginalised topic – CBD bioavailability.

What is bioavailability?

Bioavailability is a term often used in the medical world. It refers to the percentage of an administered ingredient reaching the bloodstream.

The higher the bioavailability of a particular form of application, the less of the active ingredient is needed for the effects to be felt.

You can't use CBD in a way that would allow you to achieve a bioavailability of 100%. But that's nothing unusual – you will not be able to find any supplement with 100% bioavailability.

In fact, the bioavailability of various substances depends on a number of factors – the administration process being one of them.

This means that the application method you select will impact how much of the active ingredient reaches your bloodstream; hence CBD bioavailability will be different for different CBD products.

What is CBD, and how does it work in the body? 

You are here to learn about the human body and the way CBD can interact with it.

CBD, short for cannabidiol, is a cannabinoid (a chemical compound) found in the cannabis plant.

CBD has been studied by many researchers hoping to determine if this cannabinoid can benefit human health.

For example, a recent study from a medical cannabis clinic shows that there might be a positive correlation between CBD use and a patient's general well-being, as well as improvement of moderate and severe symptoms of pain, anxiety, and depression.

While more research is needed to fully understand the impact of CBD on the human body, there seems to be a general consensus on one thing – the Endocannabinoid System.

All humans have an Endocannabinoid System (ECS), which consists of 3 players: endocannabinoids, cannabinoid receptors and enzymes.

The ECS plays a vital role in many essential processes taking place in the body through a cell-signalling system.

Scientists believe it impacts our immune system and nervous system, and may support people struggling with anxiety, pain, inflammation and sleeping problems.

How does the Endocannabinoid System work? Endocannabinoids produced in the human body send certain signals to cannabinoid receptors, which can be found throughout the entire body.

These receptors read the message sent by endocannabinoids and then react by adjusting relevant processes. Once that is done, enzymes step in and remove the endocannabinoids.

What does this all have to do with CBD?

CBD, just like any other cannabinoid, can bind with cannabinoid receptors in the same way endocannabinoids do.

This means that by consuming CBD, we might be supplementing our bodies with the plant version of endocannabinoids – cannabinoids.

Why should I care about the bioavailability of CBD?

To take full advantage of CBD and find the correct dosage, you need to understand CBD bioavailability.

CBD bioavailability represents the percentage of CBD you have used that reaches your bloodstream and interacts with your body.

CBD can be consumed in various ways, and how you choose to consume it will strongly affect its bioavailability. For example, the bioavailability of CBD oil will be different to that of CBD pills, CBD vapes, and so on. This means that by learning about CBD bioavailability, you will be able to get a better understanding of the impact CBD products can have on your body.

Fortunately, you don't need to spend hours reading biology textbooks or academic papers to understand the different levels of bioavailability of various CBD products. Instead, use this article as a quick guide to the different methods of CBD consumption and their impact on CBD bioavailability.

Different methods of taking CBD & their bioavailability

If you remember, at the beginning of the article, we explored what bioavailability means. Now it’s time to talk about the various forms of CBD application and how they impact CBD bioavailability.

Sublingual CBD: Oils & Sprays

When administered correctly, CBD oils and sprays have a bioavailability of between 13% and 19%.

The correct application requires placing the CBD drops under the tongue for around a minute without swallowing or drinking anything.

Why under the tongue?

Because this area of the mouth is highly vascular, allowing CBD (and any other ingredients in your oil or spray) to access the bloodstream quickly.

This is why many people can feel some effects as quickly as 15 minutes after consumption.

The relatively high bioavailability of CBD applied sublingually combined with its simplicity of use is the reason why the sublingual CBD application is one of the more popular methods of taking CBD.

cbd bioavailability
cbd capsules bioavailability

Oral CBD: Capsules & Edibles

People who do not always enjoy the flavour of CBD, or prefer more discrete solutions, often decide to go for a form of oral application.

In these cases, CBD can be administered by consuming a capsule (similar to most other supplements) or by eating a fun CBD edible in the form of gummy bears, cookies, chocolates, peanut butter and much more. Capsules and edibles are easy to use, but the CBD bioavailability of oral supplements might be lower than that of CBD oils and sprays.

Both capsules and edibles take longer to reach the bloodstream as they must first go through the digestive system and the liver. Only then can the CBD reach the bloodstream and get to work.

As a result, the bioavailability of CBD taken orally is usually around 6%.

Inhaled CBD: Vaping and Smoking

Whether through vaping or smoking, inhaling CBD has the highest bioavailability out of the popular methods of taking CBD. It goes as high as 31%.

This is due to the fact that both vapour and smoke can reach the bloodstream very quickly through small blood vessels in the lungs, leading to stronger and quicker effects.

But while the effects might be felt more rapidly compared to other methods of application, they will not last as long. This is why people who inhale CBD often need to do so with more regularity and consistency.

It is important to note that there has not been enough research on the long term effects of vaping or smoking CBD. In addition, the use of unauthorised vape cartridges can be dangerous, and CBD flowers are still illegal in many countries around the world.

what is bioavailability?

Topical CBD : Transdermal Patches, Creams & Balms

What about the bioavailability of CBD products that are applied directly to the skin? Well, that too depends on the type of product you use.

The bioavailability of CBD creams, gels and balms has not been researched enough to give a precise number. However, this does not mean these products are not valuable, as their purpose differs from that of oils, sprays, edibles and vapes.

CBD creams and balms are meant to have a localised effect. For example, you will not put a CBD balm on your elbows, hoping it will help you ease your anxiety. You will, however, place it on your joints and muscles after a workout, hoping it will support your post-workout recovery.

Transdermal CBD patches, on the other hand, are considered a great alternative to oral CBD applications because the patches release CBD slowly and steadily in response to the heat produced by the body. This enables CBD to skip the metabolism effect of the oral route, allowing for improved bioavailability.

While more research needs to be done, one particular study suggests that transdermal application of CBD might have a bioavailability as high as 34%-46%, suggesting this might be the future of efficient, effective and safe CBD administration

How to increase the bioavailability of CBD? Is it even possible?

Now that we have discussed different forms of CBD applications and their bioavailability, it is time to ask another important question – is there anything you can do to increase the bioavailability of CBD you take?

The short answer is yes, there is.

First of all, make sure you follow the instructions on the packaging. For example, if you use an oil or a spray, your patience will have the most significant impact on the CBD bioavailability. The longer you refrain from swallowing or drinking anything after applying your spray or oil, the more CBD will get through to your bloodstream.

When it comes to capsules – if you want to increase their bioavailability, the best thing you can do is consume them with food CBD has been shown to be absorbed 3 to 5 times more efficiently when taken with a meal containing some fat.

Last but not least, make sure you store your CBD products correctly. CBD can lose its potency when exposed to certain elements such as sunlight, oxygen or high temperatures. While this will not directly affect the product's bioavailability, it will decrease the amount of the active ingredient in the product, leading to a smaller amount reaching your bloodstream. And if you’ve had your product for a while now, make sure that it has not expired, as you should never use a CBD product after the expiry date. 

Factors that can affect CBD absorption

It is important to mention that there are certain factors out of your control that may affect CBD absorption.

People who suffer from liver issues and certain neurological disorders might absorb CBD differently from the majority of users. In addition, research studies carried out on various drugs suggest that your age, sex, and weight might impact how your body absorbs various ingredients.

Remember – if you have any pre-existing conditions, you should always ask your doctor for advice before using CBD.


Understanding CBD bioavailability is an essential part of anyone's CBD journey. By asking the right questions and finding the correct answers, it is easier than ever to use CBD efficiently and effectively. Some of the crucial questions we answered are:

What is bioavailability?

Bioavailability is a number (expressed in percentages) referring to how much of an administered substance (such as CBD) reaches the bloodstream.

What is the bioavailability of CBD?

CBD bioavailability depends on the form of administration. It is hard to know the bioavailability of CBD topicals (such as creams and gels), as not enough research has been done yet.

Inhalation (either by vaping or smoking) has a high bioavailability of 31%, followed by sublingual application (13-19%) and then oral application (6%).

Which factors affect bioavailability?

Out of the many factors affecting CBD bioavailability, the most important ones to mention are:

  • Method of application
  • Combining CBD with healthy fats
  • Health problems (certain liver illnesses, neurological disorders, gastrointestinal issues)
  • Individual traits, such as age, sex, weight, genetic phenotype