CBD stands for cannabidiol, and is one of many compounds found in all strains of the cannabis plant.
The active compounds in cannabis are collectively known as cannabinoids, alongside other groups called terpenes and flavonoids.
In Europe the hemp plant (cannabis sativa) has been grown and used by humans for thousands of years. It is naturally rich in the CBD cannabinoid and is low in the psychoactive compound THC (tetrahydrocannabinol).
CBD unlike THC is not psychoactive. This means that CBD does not change a person's state of mind when they use it. However, CBD does appear to produce significant changes in the body, and research suggests that it has medicinal benefits.
Historically hemp has had many and varied uses, including rope, clothing and paper manufacture. During the late 19th Century across Europe, hemp was used medicinally to treat muscle spasms, stomach cramps and general pain. Later it was found to help with melancholia, migraines, sleeping, and as an analgesic and anticonvulsant.
Further studies around the world in the 20th Century found many other benefits of using hemp or cannabis. But with the introduction of newer drugs and the invention of intravenous delivery, hemp fell out of favour.
The western system of medicinal patents also greatly hindered further research into cannabis, but in the 1990s scientists discovered that humans have receptors in the brain and other organs, which bind with the cannabinoids.
They named the newly discovered receptors CB1 and CB2, and called it the Endocannabinoid system. This system has an assortment of roles, regulating various functions in the body.
With much anecdotal and emerging scientific evidence of the benefits of CBD many countries are re-evaluating their position regarding cannabis.
Many States within the US have already changed their laws to allow the use of medicinal cannabis. Canada in 2018 reversed their law, and in the same year the United Kingdom is looking at allowing medicinal use for certain conditions including epilepsy.
The UK's governing body, the Medicines and Healthcare products Regulatory Authority (MHRA) stated in 2016 that products containing CBD are a medicine, and will work alongside businesses and trade associations to ensure they comply with the Human Medicines Regulations 2012.