THE BIOAVAILABILITY OF CBD
THE BIOAVAILABILITY OF CBD
Cannabidiol, commonly called CBD, is a compound naturally produced by the cannabis plant. In recent years, CBD has become very popular due to its potential therapeutic effects and its anti-inflammatory, antioxidant, anxiolytic and analgesic properties.
The world of medical cannabis and CBD is a complex world for a variety of reasons. The science and research surrounding CBD and its effects are still developing, and there is still a lot to discover regarding its mode of action and appropriate dosages.
The fact that there are many variants of CBD products on the market makes it even more difficult to understand the effects and effectiveness of each type of product. Furthermore, the fact that the CBD market is not a regulated market forces consumers to educate themselves on the topic, so that they can make the most of this interesting compound.
Different products work in different ways
When we consume CBD, it needs to be absorbed into the bloodstream, through which it will be distributed throughout the cells and tissues of the body, where it will produce its effects. More than reaching the bloodstream, it is desirable that CBD remains available in the blood for some time, before it is completely metabolized and excreted by the body.
When it comes to using CBD for therapeutic purposes, one of the concepts that frequently arises and must be understood is the concept of bioavailability. In this article, we will explain what bioavailability is and how important it is to make efficient use of CBD.
Next, we will look at the different methods of administering CBD and their respective bioavailability. Finally, let's try to understand how we can optimize the bioavailability of CBD. This information is very important so that we can make an informed choice about the best CBD product for us and so that we can get the most out of that product.
What is bioavailability?
Bioavailability refers to the amount of substance that is actually absorbed by the body and reaches the bloodstream. Once in the bloodstream, the substance can be distributed throughout cells and tissues, and exert its therapeutic action there. Therefore, the greater the bioavailability of a substance, the greater the amount of the substance that reaches the cells and has a useful effect.
For example, when we consume CBD, only a portion of that CBD is absorbed into the bloodstream and reaches our organs and tissues. After some time, unabsorbed CBD is degraded and eliminated by the body.
There are many factors that can influence the bioavailability of a substance, from its properties, which determine the way it is absorbed and used by cells (metabolized), to the individual characteristics of the consumer, such as age, sex, weight, etc.
In the case of CBD, the product chosen and the way it is administered have a direct impact on bioavailability. Therefore, different CBD administration methods imply different bioavailability. Furthermore, different methods have different results when it comes to the onset and duration of CBD's effects.
Mode of administration and bioavailability
Nowadays, we have a huge variety of CBD-based products available, as well as different ways of administering it. In this sense, we must talk about the bioavailability of CBD depending on the way in which CBD is consumed.
By definition, the bioavailability of a substance administered intravenously, that is, injected directly into the bloodstream, is 100%. Other consumption methods therefore have lower bioavailabilities.
Oral CBD
One of the most popular methods for consuming CBD (and almost anything) is the ingestion method, also called oral consumption. When ingested, CBD has a bioavailability of between 10 and 20%, and in some cases it may have lower values, around 6%.
The reduced bioavailability of CBD for oral consumption is due, firstly, to the fact that it is a very lipophilic compound, that is, with a great affinity for fats. CBD is able to dissolve in fats, but it is not able to dissolve in water.
The fact that CBD has low solubility in water means that it is not dissolved well during digestion and, therefore, has greater difficulty in being absorbed in the intestine.
Furthermore, after being absorbed, CBD is metabolized in the liver before reaching the bloodstream. This process causes part of the CBD to be degraded, greatly reducing its bioavailability.
CBD Sublingual
Another popular method of administering CBD is sublingual consumption, also called buccal use. This method involves placing CBD oil under your tongue for at least 30 seconds.
The sublingual area has a large number of blood capillaries with great absorption capacity. In this way, when administered sublingually, CBD and other compounds are absorbed by the capillaries directly into the bloodstream.
In general, it is thought that the bioavailability of CBD consumed in this way may be around 35%. It is important to note that the longer the CBD formulation is left under the tongue, the greater the bioavailability of the CBD will be, as a greater amount will be absorbed.
CBD inhalation
The inhalation method is also a popular method of consuming CBD, whether through vaporization or smoking. Inhaling CBD is the fastest way to get CBD into the bloodstream, and one with the highest bioavailability, with values between 30 and 70%. However, this mode of administration results in a short duration of effects.
Topical CBD
Topical CBD application refers to applying creams, lotions, or CBD oil itself to the skin. In this case, cannabinoids are absorbed by the skin, fat and muscles. However, it is very difficult for these to be absorbed into the bloodstream, which is why the bioavailability of topical CBD is close to zero. However, this does not mean that these products cannot produce very interesting localized effects.
Transdermal CBD
CBD products for transdermal application, such as CBD patches , are designed so that the CBD penetrates the skin and is able to reach the bloodstream, having a systemic and prolonged action. Unfortunately, there is still not much information about transdermal administration products.
We discuss CBD administration methods in greater detail here .
Increase the bioavailability of CBD
As we have already seen, different modes of CBD administration result in different bioavailability. In addition to these, a number of other factors contribute to the variability in CBD bioavailability.
Individual consumer characteristics, such as age, sex and metabolism will have some degree of influence on the way CBD is absorbed and processed by our body.
The existence of certain pathologies and the use of medications can also influence the way in which CBD is absorbed and processed, also having an impact on bioavailability.
Despite the growing interest in CBD as a bioactive molecule capable of producing beneficial effects in the body, one of the main challenges regarding the use of CBD for therapeutic purposes is its low bioavailability.
In recent years, an effort has been made to come up with strategies to make CBD more bioavailable. In this section, we highlight some of the strategies that have been shown to be effective in increasing the absorption and bioavailability of CBD.
Use a good carrier oil – MCT oil
When we talk about CBD oil, the type of carrier oil used in the formulation can make a difference in terms of bioavailability. Carrier oil is the oil in which the cannabis extract is diluted, which, after being extracted from the plant, has a high concentration of CBD and other cannabinoids.
The existence of a carrier oil is what makes it possible to produce CBD oils with a variety of concentrations. Some examples of common carrier oils are olive oil, coconut oil, and hemp seed oil.
MCT ( Medium Chain Triglycerides ) oil is a relatively common carrier in the world of CBD, and is known for its advantages in terms of bioavailability. This oil is made up of a type of fat called medium-chain triglycerides, which is normally obtained from coconuts.
Using MCT oil as a carrier oil increases the bioavailability of CBD because it increases its solubility in the intestine, facilitating faster and more efficient digestion and absorption. Furthermore, MCT oil can help protect CBD from metabolization in the liver, which, as we have already seen, contributes to the degradation of CBD molecules before they can reach the bloodstream.
In addition to being a great ally in the bioavailability of CBD, research indicates that MCT oil alone can present interesting benefits. MCT oil is a healthy oil that is not stored as fat, but rather burned for energy or converted into other beneficial compounds.
Studies point to MCT oil as a good source of energy, stating that it can help control blood sugar levels and help maintain weight. Furthermore, MCT oil may have some cognitive benefits.
Finally, MCT oil has the practical advantage of being very stable and having antifungal and antibacterial properties. This means that CBD formulations that use MCT oil as a carrier are more stable and have a longer shelf life.
Make CBD water soluble
As the human body is mainly made up of water, there is greater efficiency in the absorption of water-soluble compounds than in the absorption of compounds such as CBD, which are soluble in fats. This way, if we can make CBD more soluble in water, it will be more easily absorbed and therefore have greater bioavailability.
One of the main ways to make CBD water-soluble is to encapsulate it in small vesicles, usually emulsion particles, micelles, or liposomes. In recent years, this type of structures has had great success in the world of medicine, being used for the solubilization of several drugs and leading to an increase in their bioavailability.
These vesicles are small spherical, water-soluble structures, and are composed of two distinct parts: a hydrophilic part (with an affinity for water) and a hydrophobic and lipophilic part (with an affinity for fat).
The outer layer of these vesicles is made up of hydrophilic parts, and it is this part that is in contact with water. On the other hand, inside this vesicle, there are lipophilic parts, where CBD is contained in a natural way, since it itself is also lipophilic.
Encapsulating CBD and other hemp extract compounds within these structures presents several advantages, which contribute to greater bioavailability of these compounds.
On the one hand, the fact that CBD is encapsulated gives it greater stability and protection, and prevents it from being quickly degraded during the digestion process. Furthermore, due to the small size of the structures surrounding the CBD, its absorption will be increased.
In some cases, this type of structure allows CBD to be absorbed from the intestinal wall directly into the bloodstream via the lymphatic system. This absorption route is ideal for CBD, because it bypasses the metabolization that takes place in the liver, causing less CBD to be degraded and, consequently, a greater amount of CBD reaching the bloodstream.
Accompany CBD with a high-fat meal
When it comes to the absorption and bioavailability of CBD, the clear differences between the fasting state and the postprandial state (after a meal) cannot go unmentioned.
As we have already seen, CBD is a lipophilic substance, which means that it has a high affinity for fats. Therefore, consuming a high-fat meal before consuming CBD results in better absorption and increased bioavailability.
Being soluble in fats, when consumed with foods rich in fat, CBD is capable of dissolving in the fat of these foods, thus being broken down into smaller particles (emulsified). This way, there is a greater chance of CBD being absorbed into the intestinal wall.
In addition to being more easily absorbed, these smaller CBD particles survive in the digestive system for longer, meaning the CBD is available to be absorbed for longer.
Studies show that CBD absorption can be 3 to 5 times greater when consumed with food, compared to fasting. More than that, when taken on an empty stomach, CBD can be eliminated from the body up to 9 times faster than when taken with a meal.
It makes some sense to think that food consumption only has an impact on the absorption of CBD consumed orally. However, studies show that even when it comes to sublingual administration of CBD, absorption increases after a high-fat meal.
Increase your CBD dose
In general, we seek to increase the bioavailability of CBD with the aim of increasing its effectiveness and, therefore, increasing the likelihood of experiencing its positive effects.
Increasing the daily dosage of CBD and consuming products with a higher concentration directly leads to a greater amount of CBD reaching our bloodstream and producing its effects.
This finding is based on logical reasoning: let's imagine that the bioavailability of a certain CBD product consumed in a certain way is 50%. If we consume 100 mg of CBD, 50 mg of CBD will reach the bloodstream.
Likewise, if we consume 200 mg of CBD, then 100 mg will reach the bloodstream. In this example, even though we have increased the concentration of CBD in the blood, the bioavailability is always 50%. However, this does not seem to be what happens in practice.
Some studies indicate that the absorption and bioavailability of CBD are dose-dependent, that is, when we increase the dose, the percentage of CBD that reaches the bloodstream increases. For example, in one particular study, a dose increase from 10 to 20 mg of CBD resulted in 3 times greater bioavailability.
However, when higher doses are used, for example from 500 mg/day, this effect does not seem to occur, as increasing the dose does not result in an increase in bioavailability. This happens, in part, because tissues reach a saturation point and are unable to absorb more CBD.
Bioavailability is a factor to take into account when choosing a CBD product
Understanding the concept of bioavailability and the factors that affect the bioavailability of CBD is crucial to maximizing the potential benefits of CBD. Therefore, it is important to be knowledgeable about the products that exist on the market, and to choose high-quality products produced in a way that improves the bioavailability of CBD.
The choice of CBD administration method is a relevant factor that must be considered. In general, the inhalation method is one of the methods that has greater bioavailability, but its effects are short-lived when compared to other methods.
The best method of administration and the best CBD product depend on the individual needs and preferences of each person, and the pros and cons must be properly weighed in each case.
Consulting a healthcare professional or cannabis specialist is a good idea when we have doubts about the product, method and dose that are recommended to achieve our goals.
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