Those of us who follow the CBD market have been seeing mentions of bioavailability with regards to some of our competitor’s products. I think it would be good to explore CBD/THC bioavailability, but first let’s dive into the concept of bioavailability with definitions and examples.
Bioavailability is very simple to define and understand. Chemists and biologists abbreviate bioavailability with the symbol F which is itself an abbreviation of fraction. This is simply because bioavailability (F) is the fraction of material that gets absorbed into the systemic circulation divided by the amount of material administered. The material can be anything, from sugary drinks and protein shakes to solid foods and medicines. We can discuss, for example, the F of a common red beet. Beets are good food, with many nutrients, but there are things in a beet that don’t get absorbed (such as fiber and color) which pass through the body. The F of a beet is high, but less than one.
Bioavailability Example
Let’s now consider your favorite sugary drink. The beverage is almost all water and sugar, both of which are immediately and completely absorbed. The F of a sugar/water drink is nearly 1, about as high as one can achieve.
Now to alcohol, which has a more complicated route through the body. It, like water, is completely absorbed, so it has an F of one. But there are many different types of drinkable alcohol, from (relatively) weak beer to > 40% alcohol distilled spirits. All alcoholic beverages have an F very close to one, but they will be metabolized differently depending on how one consumes them. Sipping a distilled spirit will allow for absorption by the tissues in the mouth and esophagus, and will “go straight to your head,” since the absorption goes directly into the bloodstream without the liver metabolizing it. Chugging a beer with have the same psychological effect, but slower, and less intense. Your liver begins the detoxification immediately, thus weakening the effect somewhat. This is known as first pass metabolism, and all ingested things that make it to the stomach are subject to it. So, while F is ultimately the same by doing a shot or sipping a beer, the amount of alcohol in your bloodstream depends on liver metabolism.
Metabolism
Metabolism is one of the four concerns for the medicinal chemist. The gauntlet a medication needs to survive clinical testing (aside for being efficacious) is called ADME, short for Absorption, Distribution (where the drug goes after consumption), Metabolism and Excretion.
I digressed from F to more complex topics. That’s how we learn. Back to bioavailability.
The examples above (alcohol or sugar in water) are examples of compounds with very high F. Both materials are very water soluble, thus easy to pass though the gut. Molecules that are not water soluble either pass though the gut via active transport (cholesterol for example), or are slowly absorbed as lipids in the intestine.
Cannabinoids have a very low F. Swallow some CBD or THC concentrate on an empty stomach, and chances are that the medications will pass right through you with no effect. Now, have a high fat meal (Burgers or Pizza), and the situation is totally different. The cannabinoids are absorbed with the lipids in the food. This is known as the food effect, and it is an important element to consider when taking cannabinoid edibles.
The effect of food is opposite in the case of alcohol and cannabinoids. An empty stomach will get you drunk quicker than after-dinner drinks. A full stomach blunts and slows the absorption of alcohol, but has the opposite effect on cannabinoids, which get absorbed with your meal.
So: don’t drink alcohol or take cannabinoids on an empty stomach. Both are buffered by food, allowing for good absorption without stomach upset.
Our full spectrum organic CBD oils are formulated for either sublingual (under the tongue) or oral consumption. Take with food for maximal effect. Better yet, use the oils in cooking, so the food and the medicine are already mixed.