E-liquids, oils, capsules, cosmetics… CBD can come in all sorts of shapes and sizes. Beyond personal preference, each consumption method has its advantages and disadvantages, especially in terms of bioavailability.
CBD bioavailability: the definition
In pharmacology, the bioavailability of a molecule covers two characteristics:
- The speed at which a molecule reaches systemic circulation
- The proportion of the administered dose that reaches systemic circulation
Put simply, it can be described as the percentage of the consumed substance that really reaches the blood quickly enough to have a measurable effect.
A molecule’s bioavailability varies according to the route of administration, meaning the way in which it is consumed. Depending on the properties of the molecule, its bioavailability will be higher or lower orally, through inhalation, or even cutaneously. By definition, the bioavailability of a molecule can only be 100% when it is administered intravenously, which is why this route of administration is limited to a strictly medical context.
The different CBD bioavailability rates
Like any other molecule, CBD’s bioavailability varies according to how it is consumed. The two main CBD routes of administration are ingestion and inhalation.
Through ingestion or sublingually
When ingested as an oil or capsule, CBD’s bioavailability is low. According to research, it is around 8%. With this route, the CBD molecules need to cross most of the digestive system before reaching systemic circulation. What’s more, they are broken down by the enzymes produced by the liver and stomach during digestion. This alters the effects of the CBD.
The best oral route of administration is therefore sublingual, which involves placing the CBD oil directly under the tongue. This way, the CBD absorbs more quickly and its effects last longer.
CBD cosmetic products allow you to consume the molecule through your skin. The bioavailability of CBD consumed this way is quite low in terms of speed, but the molecule is altered less than it would be by ingestion. The main thing is to find the right material, or vehicle, to allow the molecule to penetrate your skin.
Like nicotine, CBD seems to have optimal bioavailability when inhaled. It can be as high as 20%, twice as high as when it is ingested. As CBD liquids are the only legal way to inhale CBD, they are the solution with the best bioavailability.