In 1928, fearing a collapse in morality, cannabis was made illegal in the UK. It was still legal for doctors to prescribe cannabis oil (cannabidiol or CBD) for medical purposes, but at the start of the Seventies this too was outlawed, and science lost a powerful medicine.

The timeline was a little different in the USA. Cannabis was banned state by state, starting with Massachusetts in 1911, and at federal level with the Marihuana [sic] Act in 1937. In some states it was obligatory that those convicted of possession lost their driving license, whether the circumstances had involved driving or not.

People – from ordinary folk to scientists – started to point out that cannabis oil had been used as a medicine for hundreds, possibly thousands, of years. Patients with significant ailments were being denied an effective and innocuous treatment. In recent times there has been extensive press coverage of children with very serious conditions who appear to have benefited hugely from treatment with CBD.

A landmark in the study of cannabis came in 1960 when the Israeli chemist Doctor Raphael Mechoulam successfully isolated the CBD compound. His experiments separated it from Tetrahydrocannabinol (THC) – the element which gets users high. CBD has none of the properties of marijuana and cannot get you high under any circumstances.

Extracted from a specific strain of the hemp plant (cannabis sativa), CBD has been mentioned in texts many times over the centuries. The hemp plant itself has had many uses, from rope to clothing, and from fuel to animal feed. Henry Ford even experimented with making car bodies out of hemp.

Hemp has been spun into fibre, rather as cotton is, for at least 10,000 years. CBD was used to ease cramps and pains in ancient Chinese times – as well as to ease more serious complaints. It is documented as being an important crop in the Iberian peninsula in the 1300s, and was a staple crop in Tudor England. The first British settlers in America took it with them and grew it there with great success.

Many famous sportsmen and women have endorsed the efficacy of CBD oil for a range of ailments, as has the actors Tom Hanks and Jennifer Aniston. Whoopi Goldberg says that it helps greatly with period pain and coping with stress. Morgan Freeman takes CBD to counter the pain incurred during car crash.