Whether you are a new CBD user, or have been using CBD in one form or another for years already, one factor that plays a very large role in how CBD affects you is bioavailability. Phytocannabinoids, including CBD, originate from the botanical kingdom and stimulate your endogenous endocannabinoid system (ECS, for short). The ECS is a complex set of neurotransmitters, neuroreceptors, and cellular enzymes that help to maintain homeostasis in your body. In order to be effective, phytocannabinoids like CBD need to become available to your ECS.
Bioavailability refers to how much, and at what rate, a substance gets absorbed by your bloodstream. You may wonder how much of a CBD product is actually absorbed and used by your ECS. The answer depends largely on two factors, the type of CBD extract (isolate, full-spectrum, broad-spectrum, etc.) and the delivery method.
Bioavailability of CBD Tinctures
When CBD-rich hemp extract is taken sublingually, held beneath the tongue, or buccally, held between the cheek and gums, CBD has a bioavailability ranging from 13% to 35%. Holding an extract beneath the tongue or on the sides of one’s cheek for 10 to 60 seconds allows enough time for the CBD to be absorbed through the mucous membranes lining the mouth, and to quickly enter directly into the bloodstream. This method offers better bioavailability over oral ingestion since it doesn’t pass through the digestive system, thereby avoiding first-pass metabolism, where cannabinoids get broken down by the liver. Since phytocannabinoids are fat-soluble, there is evidence that suggests that using CBD in a saturated fat carrier oil, such as MCT oil (medium-chain triglyceride oil) can increase the bioavailability. MCT’s are a type of dietary fat with a unique chemical structure compared to longer-chain fats, which absorb easily in the body, providing fast energy and quick delivery of cannabinoids to the bloodstream and brain.
Bioavailability of CBD Edibles
Oral ingestion of CBD is another option, and is perhaps the most popular because it involves regular daily activities like eating food, drinking beverages, and swallowing vitamins. Absorption ranges vary widely between 4% to 20% for ingestion. When you orally ingest CBD edibles or supplements, the CBD must pass through your normal digestive and metabolic systems, which filter out a large portion of the CBD before it ever reaches your bloodstream. CBD’s solubility makes it challenging to get past these systems to your bloodstream. CBD is lipophillic, which means it combines with lipids and fat. With this in mind, the bioavailability of a CBD edible can be increased by consuming it with lipids, such as MCT oil or cacao butter. Combining CBD with these natural dietary fats and lipids makes the mixture even more lipophilic (fat-loving), driving absorption to the chylomicron-lymphatic absorption path, which increases the overall bioavailability versus absorption via the hepatic (liver) portal route (system for absorbing hydrophilic [water-loving] substances from the gut to the liver). In one study, consuming a standard breakfast one hour before consuming CBD capsules increased bioavailability. This study demonstrates how combining CBD with lipid and fat-rich foods helps increase the effectiveness of CBD through oral ingestion.
Edible options can also be enhanced by combining phytocannabinoids with other functional ingredients. Terpenes are a good example, they’re the natural compounds found throughout the botanical kingdom that help to stimulate the brain’s neurotransmitters. Black pepper, oregano, cinnamon, and clove all contain the terpene beta-caryophyllene, and are known to stimulate the CB2 receptors, which are the same receptors that phytocannabinoids bind to. Foods like galangal, maca root, and chocolate, inhibit fatty acid amide hyrolase (FAAH), which allows the “bliss molecule” known as Anandamide to prolong in your system. Anandamide is a powerful neurotransmitter that carries phytocannabinoids to the ECS receptor sites. Additionally, researchers have recently concluded that natural fats in chocolate facilitate a process called lipid micro-encapsulation. This protects the CBD molecules during digestion, resulting in larger quantities of CBD being delivered to your bloodstream. This is why CBD Chocolate is Vital Leaf’s edible of choice. We source the most anandamide-rich cacao in the world from our regenerative farmers in Ecuador. You can read more about that in our article, CBD Chocolate and Its Effect on the Brain. We recommend letting Vital Leaf chocolate melt in your mouth, not only can you increase your pleasure, but it can also increase the oromucosal and sublingual absorption too!
There are also some more cutting-edge options that can be employed to increase the bioavailability of orally ingested products containing CBD, such as utilizing nanoparticle technology. Since humans are mostly made up of water, nutrients that are soluble (dissolvable) in water pass more easily to the bloodstream. Phytocannabinoids that are lipophilic (oil-based molecules that are not soluble in water), like CBD, have difficulty dissolving and absorbing in the body versus a water-soluble nutrient. Nano-enhanced or biocellular micellization is a way of rendering the particle size of the CBD and other phytocannabinoids into a much smaller or even nano-particle size, then binding it to a liposome. Liposomes are small spherical vessels that transport substances into the body that prevent breakdown by stomach acid and facilitate quicker delivery and higher absorption into the bloodstream. At Vital Leaf, we utilize this biocellular micellization technology in combination with soluble rich organic acacia fiber (from the sap of the Acacia senegal tree) in our CBD Capsules. Micellization technology improves absorption rates up to 3-5 times compared to conventional or standard products.
Bioavailability of CBD Topicals
Topical CBD products such as balm, lotion, cream, spray, or roll-ons are best used for targeting specific localized issues on the body. CBD that is applied topically doesn’t actually enter into the bloodstream, so it is difficult to determine how much is absorbed. Remember, bioavailability refers to how much, and at what rate, a substance gets absorbed by your bloodstream. Transdermal products, which are often found in the form of patches, are the exception for topicals, as they employ technology for deeper sustained penetration that can reach the bloodstream. Typically topicals do not go into the bloodstream though and are instead absorbed into the skin’s surface, interacting with local cannabinoid receptors in the epidermis and subdermal areas. CBD topicals can benefit from the addition of other therapeutic botanicals found to assist with reducing tension and nourishing the skin. Vital Leaf’s CBD skincare is formulated with powerhouse botanicals like shea butter, coconut oil, arnica, frankincense, lavender, cardamom, along with our phytocannabinoid-rich CBD hemp extract.
Bioavailability of Inhaling CBD
The CBD delivery method with the highest absorption rate is inhaling through the lungs. Bioavailability is between 34-46%, although some studies have reported rates as high as 56%. The lungs are lined with delicate tissues, and when smoke or vapor is inhaled it goes directly into the bloodstream. Smoking and vaping provide nearly immediate results and can be a good short-term relief option. Not everyone feels comfortable with this administration route though and there can be other drawbacks and health concerns with both smoking and vaping. There are not enough long-term studies of whether vaping can cause damage to the delicate lung tissue. It’s important to note that some inhalant products can contain hidden ingredients and sometimes microparticles that can embed deep in the lung tissue, along with harmful chemicals, heavy metals, synthetic fragrances, or flavor enhancers.
To learn more about the different CBD delivery methods or to better understand how to identify the right CBD dose for your needs, we suggest the following articles.