CBD bioavailability

CBD Bioavailability: How to Optimize CBD Absorption

It seems like everywhere we turn these days, a new CBD product is popping up. The versatility of this cannabinoid has manufacturers looking for innovative ways to consume it.

With CBD, the sky is the limit—you name it, the CBD industry’s got it.

Today, you can find CBD infused in almost everything—from lattes to body care, from sexual lubes to cocktails, to dog treats and beyond.

But before these products can provide their benefits, your body has to use them well. The product you choose and the way you take it determine how fast and effective it is to provide relief. This is known as “bioavailability,” and every type of CBD product has a different one.

In this guide, I will cover all the basics about CBD bioavailability and how to get the best out of it to maximize absorption.

Table of Contents

First things first, do you know…

What Is CBD?

CBD is the moniker of cannabidiol, one of the hundred compounds present in the cannabis plant. Cannabis has many varieties and names but the most prominent these days are hemp and marijuana.

Both varieties produce CBD which is classified as a “cannabinoid” for its ability to interact with certain receptors of your body. CBD is a non-intoxicating molecule, meaning it won’t alter your mind and reasoning.

Actually, the cannabinoid that gets you high is tetrahydrocannabinol or THC. This chemical is infamous not only for its mind-altering effects but also because it determines if a cannabis variety is hemp or marijuana.

Anything with less than 0.3% THC content is considered hemp and is federally legal in the 50 states of the union. Marijuana, on the other hand, has higher amounts of THC, some strains can go up to 30%. Marijuana is legal in 11 states but remains as a Schedule 1 controlled drug at federal level. That’s why most of the CBD on the market is hemp-derived.

Cannabidiol is known as an anti-inflammatory molecule, but the hardest evidence supporting the benefits of this cannabinoid is related to seizures. In fact, the only CBD product with FDA approval is a drug to treat a rare form of epilepsy in children. However, preliminary studies and countless testimonials are praising the use of CBD for a wide variety of illnesses, aches and pains.

According to the New York Times:

With more than 65 cellular targets, CBD may provide a kind of full-body massage at the molecular level.

CBD may be able to provide support for:

  • Healthy neural stem cell growth to give you a “young again” brain 
  • Healthy brain cells
  • Healthy heart 
  • Healthy state of mind
  • Healthy blood pressure 
  • Comfortable joint function
  • Healthy pancreatic b-cells, to promote healthy insulin levels
  • Healthy blood sugar 

Among many others, but the truth is…

CBD is a promising molecule with potential medical value but not a cure-all. A lot more research is needed to actually know what it really can do.

If you’re already on the CBD loop and want to know how to get the best out of your product, then you should know…..

What Is CBD Bioavailability?

CBD bioavailability refers to the amount of CBD that goes into your bloodstream and how much of it is actually absorbed by your body to provide an effect. Bioavailability is measured in percentages (%).

CBD is a hydrophobic molecule. In other words, it’s non-water-soluble. We live in watery bodies, which makes it difficult for CBD to be absorbed. Tha’s why knowing the bioavailability of your product matters.

The efficacy of a product depends on its bioavailability, and it varies based on:

  • The way the product is delivered in your body.
  • The emulsion type: water and non-water-soluble CBD.
  • The type of CBD: full-spectrum, broad-spectrum, or isolate.
  • The CBD concentration in the product you’re taking.
  • The time the product remains in your system—active or dormant.

This leads us to one fundamental question:

How is CBD Absorbed?

The way you take your CBD—orally, inhaled, topically, etc.—is known as the “point of introduction.”

After ingestion, CBD travels from the point of introduction to the body before it can get into the bloodstream. This journey is called the route of administration. CBD is absorbed like any other drug: it must pass through several barriers before reaching the bloodstream.

Once in the bloodstream, only a small portion of the CBD present in the product is transported throughout your body to stimulate different receptors and unleash its therapeutic effects.

The routes of administration for CBD:

  • Injection
  • Inhalation
  • Oral
  • Sublingual
  • Transdermal
  • Topical


If CBD is injected, it directly enters the venous system and is transported to the heart. Then it travels to the lungs and finally come back to the heart to be distributed throughout the rest of your body.

This is currently the only route of administration that provides 100% bioavailability, but it’s not without downsides: sticking a needle in your body for every dose is painful, and CBD injections are a rare find.


If CBD is inhaled, it goes directly from the lungs to the heart. Then it leaves the heart through the aorta—the major artery in the body—to be distributed throughout the rest of the body.

Inhalation is fast because of the huge amount of capillaries in the lungs. It includes both smoking and vaping.


Smoking CBD flower roll-ups is the traditional way to get it into the lungs, and it has an average bioavailability of 30%, according to the pharmacokinetics of cannabinoids study.

Bioavailability of cbd flower roll-ups


Vaping is the “cool” way to inhale CBD; it’s not only trendy but is also fast and effective. The bioavailability of these products ranges from 35 to 45% and can go as high as 55%. However, as fast as the relief is provided, it goes away just as quickly. Depending on the potency of the product, the effects last from 45 minutes to only two hours.

What you inhale from a vape pen is a juice especially crafted to produce a vapor with minimum gunk, which differs from the oils you take orally. The CBD in these vape juices is usually mixed with other chemicals that are dangerous for the delicate lining tissues of the lungs.

That’s why vaping might be a bad idea: it exposes the lungs to other harmful fumes that are associated with lung disease.

Use the pen in moderation. A smart move is to leave it for occasions where immediate relief is needed.

Bioavailability of CBD vapes—infographic


If CBD is ingested orally, it has to pass the first-pass metabolism. So, the compound gets to the stomach, passes into capillaries in the gut, and then travels to the liver, where it’s metabolized by enzymes.

From the liver, CBD goes through the venous system to the heart, then to the lungs. Then it returns to the heart to travel to the rest of the body.

As you can see the journey through the digestive tract is long, and it slows down the absorption of your CBD.

The oral route includes gulping down CBD capsules or ingesting infused food and beverages. The problem with infused edibles



Body cavities have mucus-secreting membranes full of tiny blood vessels (capillaries) and they’re very numerous. Capillaries have tons of pores that allow molecules like CBD to easily pass through and get into the bloodstream, avoiding the first-pass metabolism.

The CBD products that can target the mucosal lining are sublingual drops, nasal sprays, rectal, and vaginal suppositories.


These products come in the form of tinctures and oils. The difference between them is the base, tinctures have an alcohol base while oils are mixed with carried oils to make them more bioavailable.

As the name implies, the point of introduction of sublingual drops is the capillary-rich areas under the tongue. There are capillaries along the cheeks and gums too. Basically, you put a few drops of CBD under your tongue and let it sit for 30-60 seconds before swallowing.

Bioavailability of these products can be between 15-35%, and effects can last 5 hours.

Eating, drinking, or smoking, can affect how sublingual CBD is absorbed and how effective it is.

Bioavailability of sublingual drops—infographic


These products are usually a water-soluble form of CBD. Nasal delivery results in greater absorption, meaning you can take much smaller doses for the same effects.

There’s a lot of vascularity in the nose that helps CBD go right into the bloodstream. From there, it quickly travels to the brain and other target areas within the body.

Bioavailability for nasal sprays is similar to inhaled CBD—some products are reporting rates up to 80%—but without the health risk of the vapes.

nasal spray bioavailability


Pushed through the anus or vagina, CBD suppositories aren’t everyone’s cup of tea but they’re very effective to provide local relief. The lining walls of these areas are rich in capillaries, so CBD can also enter the bloodstream bypassing the first pass metabolism.

Research shows that this route has 25 to 50% more bioavailability than oral administration.

Bioavailability of CBD suppositories


Although the skin barrier is difficult to overcome, some CBD products are specifically crafted to be able to pass through the small spaces between the cells of the skin.

These products are designed to release the compound for several hours, sometimes even for several days. CBD for transdermal delivery must have high potency, because the penetration rate and area of application are limited.

In a randomized clinical trial transdermal administration showed great results in decreasing pain in patients by 70.2%.

The transdermal delivery of CBD bypasses the digestive tract and gets to the heart directly from the bloodstream.

CBD trasdermal patches—infographic


CBD’s bioavailability rates through your skin are very low. This method is used for local relief only because the dermal barrier doesn’t allow the active compound to enter the bloodstream.

However, the skin has plenty of cannabinoid receptors that interact with the CBD infused in topical products.

Bioavailability of topical CBD

I bet you’re wondering…

Which Route of Administration Is Better?

Ultimately, this is totally up to you and your needs. To figure out what product suits you better, you need to undergo a bit of self-experimentation. Sublingual drops are the best way to start on CBD.

Once you determine the minimum amount of drops that brings you benefits, it’s safe to combine different methods like inhalers to find out if you’re more into a fast-acting solution or a slow-burner.

Don’t forget to add another method after your initial dose wards off. Pay attention to your body, watch out for side-effects, and control your dosage when combining these products.

Here’s a recap of the bioavailability of the methods discussed before:

  • Injectables: 100%
  • Vaporizers : 30-56%.
  • Oral: 6-19%
  • Sublingual drops: 15-35%
  • Nasal sprays: 30-80%
  • Suppositories: 25-60%
  • Transdermal: 30-70%


As CBD has gone mainstream, brilliant scientists and manufacturers are working hand in hand to create new and more absorbable products.

CBD is a fatty molecule, and the average adult is about 60% water. You know that oil and water don’t mix, so it makes sense to transform the naturally oil-soluble CBD into a water-soluble form.

Water-soluble CBD is a form of CBD that goes through a process of emulsification to make it more “water-friendly.” The result is a powder or liquid that can be used to produce tinctures, capsules, edibles, topicals, and drinks.

The main purpose of water-soluble CBD is to overcome the extensive human first-pass metabolism, which—as we already learned—is the barrier that oil-soluble products face when they pass through the digestive system, leaving them with poor bioavailability rates.

The processes to convert CBD into a water-soluble extracts use surfactants as the chemical agents that make the compound molecules smaller and water-compatible.  These methods are the following:


Liposomes are water-containing bubbles that can mix with both water and fat. They attach to, encapsulate, and protect the CBD molecules, to make them easier to absorb. But this process requires high amounts of surfactants and highly complex manufacturing procedures.

Liposomal CBD is very popular in the hemp industry, and its bioavailability rates are about 20% greater than standard products.


This process isn’t common in the CBD industry because it requires a lot of surfactants, which is not ideal for your health and come with side effects. Make sure your CBD is NOT a micro-emulsion extract.


This method breaks down CBD molecules to make them extremely small or “nano-sized.” This process is considered as a safe and effective delivery system that uses a low amount of surfactants to brake CBD into particles that are smaller than a grain of sand.

Bioavailability of the nano products can be increased by 50%, which makes them most cost-effective than similar oil-based products. The downside? Some brands are taking advantage of the fancy “nano” term to draw attention with products that contain fake “nano-sized” molecules .


The type of CBD also affects its bioavailability. Hemp-derived CBD falls under three categories that refer to the components present in your product, and they are full-spectrum, broad-spectrum and isolate.

Hemp is home to many chemicals beyond cannabinoids, it also produces terpenes—which are the aromatic compounds that give the plant its distinguishing aroma—flavonoids, fatty acids, ketones, enzymes, amino acids and chlorophyll.

All of them have different  therapeutic effects, and they all work together in synergy. Synergy increases their individual strengths, enhancing the way each compound benefits your body, counteracting their untoward effects, and also promoting their absorption.

“Synergy – the bonus that is achieved when things work together harmoniously.”

—Mark Twain


Full-spectrum products are made from whole hemp plants. Nothing is added or removed from the hemp’s natural chemical composition. These products also contain THC, usually less than 0.3%. The CBD bioavailability of these extracts is greater thanks to the synergistic interactions of the other compounds present in hemp.


products account for whole plant THC-free stuff; they go into a distilling process that removes the compound that gets you high. Terpenes and flavonoids from hemp raise CBD bioavailability and also enhance the therapeutic effects of this cannabinoid.


As its name says, Isolate formulas only contain CBD, these extracts have the lowest bioavailability rate.


How to Optimize the Absorption of your CBD

We all want to get the best out of CBD; however, you can’t change the bioavailability of a product. What you can do is to help your body to absorb you it better.

You can boost CBD absorption in the following ways:


There’s no one-size-fits-all way to take CBD, and you should pick your method of consumption depending not only on its bioavailability but also on your health goals. For instance, if you’re having a panic attack or excruciating acute pain, you need fast-acting relief from vaporizers or nasal sprays.

For day-to-day wellness, sublingual drops and capsules are a better choice, despite the lower bioavailability rates, because the effects last longer.

If you have pelvic pain, vaginal suppositories deliver the highest concentration of CBD exactly where you need it.


This can be as easy as trying a different inhalation technique or holding your sublingual drops under your tongue for another 30 seconds.


As noted above, picking a full or broad-spectrum formula can enhance CBD absorption because the bioavailability is better.

Hemp is better than the sum of its parts. Terpenes, fatty acids, and flavonoids act like CBD’s support crew. They enhance not only its benefits but also speed up the way this cannabinoid get into your bloodstream, facilitating its absorption and keeping it effective for longer.


Emulsified or “nano” CBD has better bioavailability rates and faster onset of its therapeutic effects than standard CBD. Before your body filters out the nutrients from the CBD molecule, nano CBD is able to be completely absorbed.

Thus you will need a less amount to get the same effects that you get with standard CBD. In other words, you get the best bang for your buck.

But set your BS meter on when choosing a nano product, since there’s a lot of deceit on the market and the “nano” term is a buzzword used to draw attention with products that don’t contain real nano-sized molecules.


The concentration of the product depends on the strength of CBD you’re purchasing, You can find on the market oils with concentrations starting at 100 mg and up to 1500 mg per bottle. The higher the concentration the greater bioavailability.

Make this decision depending on your condition and how much CBD per serving is really effective in terms of relief.


There are natural and cheap ways you can use at home to increase the absorption of your CBD.

Your standard CBD is a fat-soluble compound. Fats and fatty oils make it easier to absorb by breaking the compound down into smaller molecules. Because of this, you can optimize CBD’s absorption if you take it with a high fat meal. Just make sure you’re picking healthy fats for overall well-being.

A good, balanced diet doesn’t hurt bioavailability, but experts have found that after a high-fat meal, the amount of CBD in the body rises.

It can be four times greater with a maximum amount in the blood of 14 times higher than in patients that take CBD in a fasted state. This means a lower dose and, therefore, a lower cost.


For millennia, honey has been used as a vehicle to deliver herbal medicine because as a simple carbohydrate, it enters the bloodstream easily. Mixing honey with CBD could be an effortless way to get all the health-giving benefits of these compound and feel almost instant effects.

Honey can be the perfect CBD partner, as it also provides energy-boosting effects, it’s rich in antioxidants, it has a positive effect on cholesterol levels, and, of course, its delicious taste.


Spices not only add a lot of flavor to your foods, they also have therapeutic benefits. One of those benefits is enhancing the absorption of different nutrients. Some of the spices that can increase the absorption of your CBD are:


Black pepper is the “king of spices.” It was a valuable good for international trading between India and Europe five hundred years ago. Men traveled around the world and even discovered a new world looking for it.

Today, this spice is used in nearly every kitchen around the world. Black pepper not only adds flavor to your food, but it also has many health benefits, and one of them is that it can increase CBD’s absorption.

Black pepper contains terpenes, and terpenes are the aromatic compounds that raise CBD bioavailability.

Piperine is the major bioactive component of black pepper known for its ability to increase the absorption of nutrients within your body. Piperine is mostly used to enhance turmeric absorption, and its gaining recognition in the CBD industry because it can increase the bioavailability of this compound.


Cayenne—the “American spice”—contains capsaicin, which is structurally similar to CBD and targets the TRPV1 receptors, the same receptors that CBD impact to control pain perception. 

Capsaicin and CBD has a strong synergistic potential via mutual effects at these receptors. Capsaicin is easily absorbed and can help increase the absorption of CBD.

Final Words

There’s more than one way to enhance the absorption of your CBD, whether you use a method with higher levels of bioavailability, get a fancy emulsified product, mix your CBD with a fatty snack or combine it with spices.

But as everyone is unique, prepare yourself for a bit of self-experimentation to find the best way to take your CBD to make the most out of it.