Cannabinoids 101

by Tom Russell May 03, 2020

Cannabinoids 101

Cannabinoids are most commonly found in cannabis plants but can also be found elsewhere. They are present in most animal species as well as in plants like the cacao tree, echinacea and helichrysum.

When consumed by humans, they interact with a network of receptors found in our nervous system. Different cannabinoids affect the receptors in different ways, producing a range of varied effects. Some, like THC, are intoxicating, but most are not.

What are cannabinoids?

Cannabinoids THC and CBNCannabinoids are substances that are similar in structure or function to those found in cannabis plants. They are found throughout the natural world but of the hundreds of chemical components of cannabis, over 100 are cannabinoids. 

The first to be discovered was cannabinol (CBN) which was extracted from cannabis oil at the end of the 19th century. Much later, in the 1930s, its structure was described by chemist R.S Cahn. Since then, more have been found and named, including CBD and THC.

CBD and THC are the most well-known cannabinoids. THC gives cannabis its intoxicating properties and produces a sensation known as a 'high'. In many areas of the world, including the UK, cannabis strains containing more than 0.2% are illegal to grow because of this effect. CBD is psychoactive however, it is non-intoxicating.

Cannabinoids are also present in some plants and the bodies of most animal species, including humans, mammals, birds and reptiles. To distinguish between those found in animals and those found in plants, chemists use different names:


Phytocannabinoids hemp plantThese are the cannabinoids produced in plants. 'Phyto' means 'of a plant' and comes from the Greek word for plant 'φυτό'. Chemists and botanists know little about why plants produce chemicals like cannabinoids, but there are a few theories. The main one is that they aid the plants' survival.

They could carry out several functions, including:
– Protection from UV light
– Deterring insects
– Attracting pollinators
– Preventing water loss
– Preventing overheating

    Whatever their function in plants, they provide an incredibly broad range of effects when consumed by animals.


    Endocannabinoids are known to be present in humans but are also found in most animals. Endo is short for 'endogenous' which means 'originating from within an organism'. They are produced inside animal bodies and are present in most internal tissues. 

    Anandamide (arachidonoyl ethanolamide) and 2-arachidonoyl glycerol (2-AG) were the first endocannabinoids to be discovered. Both carry out several functions in your body and are involved in important chemical signalling mechanisms.

    What do cannabinoids do to your body?

    ESC receptors cb1 cb2Phytocannabinoids interact with your body via your endocannabinoid system (ECS). This is a collection of chemical receptors, endocannabinoids and enzymes that are present in your nervous system. They assist with the transmission of chemical messages to keep your body systems in balance.

    This internal balance is known as homeostasis and it is maintained by several chemical mechanisms. If something in your body changes, such as your temperature, it triggers a homeostatic mechanism. This sends a signal to the necessary systems in your body to bring it back to normal.

    For example, if your temperature rises, you start to sweat and your heart pumps faster. This brings your blood closer to the surface of your skin and cools you down. Homeostasis applies this balancing response to everything in your body, so it’s instrumental in how your body responds to illness and injury.

    Each cannabinoid from the cannabis plant has a different way of interacting with your ECS receptors and produces a different effect. Some research indicates that interaction with this system can boost the speed of your body's response when systems fall out of balance. Some cannabinoids, like THC, bind directly with ECS receptors while others interact via endocannabinoids or enzymes. 

    What are synthetic cannabinoids?

    synthetic cannabinoids fake leafSynthetic cannabinoids are artificial chemicals that can interact with the human endocannabinoid system. They were first created to help scientists explore cannabinoid structure and investigate the function of the ECS.

    During this research hundreds were created, some went on to be used as medicines and others became known as legal highs:

    – Dronabinol is a synthetic cannabinoid that is used to treat weight loss and nausea.
    – Others and were found to form part of the notorious drug ‘spice’. Originally sold as a legal version of cannabis, it was found to have extremely harmful effects and is now illegal in the UK. 

      More recently, synthetic cannabinoids have been produced biologically using genetically modified organisms such as yeast. Biosynthetic cannabinoids are usually chemically identical to the original. In 2019, scientists announced that they had successfully created biosynthetic versions of CBGa, THCa, CBDa, THCVa and CBDVa.

      What are the common cannabinoids?

      The most common cannabinoids are those that are abundant in cannabis and hemp extracts. More is known about them because they are easier to detect and extract. 

      During the life of a cannabis plant, cannabinoids are created and change into different forms. Some cannabinoids become other types as the chemical conditions in the plant cells change.

      Cannabinoid acids

      Initially, cannabinoids are present in the plant in their acid form, such as cannabidiolic acid (CBDa). But if enough heat is applied, they decarboxylate to become the more commonly recognised versions. For example, CBDa decarboxylates to become CBD and THCa becomes THC.


      Cannabidiolic acid is the precursor of CBD and is present in CBD rich hemp varieties. It doesn't bind directly with the ECS receptors but inhibits nearby enzymes.  

      Studies have shown that CBDa is likely to increase levels of serotonin, but currently, there are no well-publicised human studies of CBDa.  


      Tetrahydrocannabinolic acid is the most prevalent cannabinoid acid in psychoactive strains of cannabis. It's non-intoxicating, but decarboxylation produces the highly psychoactive THC. If taken in its raw form, THCa, like CBDa, acts as an enzyme inhibitor.


      Cannabigerolic acid is crucial to the production of several other cannabinoids. In cannabis plants, it can form THCa, THCVa, CBDa and CBCa. However, if decarboxylated, it creates CBG.

      Very little is known about the chemical function of CBGa, but research indicates that it may inhibit another set of enzymes present in body tissue.


      Cannabinolic acid is the acidic form of CBN, and it often occurs when cannabis bud is exposed to the air for an extended period. Under these conditions, THCa is converted to CBNa. There is speculation that CBNa may exhibit similar effects to CBN and THCa.


      Cannabidivarinic acid is found in more considerable amounts in Indica strains of cannabis. ‘Indica’ refers to varieties that initially came from areas like India, Nepal and Afghanistan.


      Tetrahydrocannabivarin carboxylic acid is produced when CBGa breaks down. THCVa is one of the substances detected during drug testing. It’s used as a marker to identify if someone has been using illegal strains of cannabis. It's a non-intoxicating cannabinoid, and when decarboxylated, forms THCV.

      Decarboxylated cannabinoids 

      Decarboxylation can occur instantly if the cannabinoids are ignited or vaporized. If heated it starts at about 104˚C and can take from 30 minutes to 2 hours.


      Because CBGa, the acid form of CBG, is often converted to other cannabinoids before decarboxylation, CBG is usually only present in tiny amounts. However, some scientists believe it to have valuable benefits that make it worth researching. To do this, breeding and genetic manipulation have been used to create varieties of cannabis with higher levels of CBG.


      The psychoactive effects of THC are the most well-known aspect of the cannabis plant. In many areas of the world, the legality of hemp products is determined by how much THC they contain. In the UK, a CBD oil must have less than 1mg of THC per container to be legal. Despite THC and CBD both being abundant in cannabis plants, they have very different effects. CBD is non-intoxicating and won't get you high.


      What does CBD stand forCBD refers to cannabidiol. CBD doesn’t bind directly with ECS receptors but prevents enzymes from breaking down the endocannabinoid anandamide.

      In the UK, and elsewhere, CBD has become the most talked-about food supplement in recent years. The World Health Organization has stated that it has a good safety profile and the potential to be generally beneficial to health. The cannabidiol extract used for CBD products is extracted from hemp, a variety of cannabis that is low in THC. It is known for the ease with which it can be added to an ever-increasing range of food supplements and functional drinks. 


      Cannabinol is present in cannabis that has been allowed to age. It can be intoxicating when taken in large amounts and, in the UK, is also restricted to 1mg per container in CBD products. There is very little research on CBN, and little is known about how it interacts with the ECS.


      Cannabichromene, like CBD and THC, is formed from CBGa. It doesn't bind with the primary ECS receptors, but it does interact with others present in the peripheral nervous system. It may also be responsible for raised levels of anandamide and 2-AG. It is believed that the most significant effect of CBC is when it's taken alongside other cannabinoids


      Cannabidivarin is found in higher levels in Indica strains of cannabis and in those particularly rich in CBD. Some animal studies indicate that it may have beneficial properties as strong as those of CBD.


      With a similar structure to THC, tetrahydrocannabivarin is also intoxicating. Early studies indicate that it may behave slightly differently to THC and produce a range of useful benefits.


      Cannabinoids play a larger role in our lives than you may think. They are present in a range of plants and are a crucial part of some of the actions of our nervous system. Many benefits have been discovered, but we are only at the threshold of most of what they have to offer.

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      Tom Russell
      Tom Russell


      Tom Russell writes extensively about CBD oil and other groundbreaking food supplements. He and his wife share their home with two daughters and a lifetime’s collection of books.

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