Love Hemp has been selling cannabis-based supplements legally in the UK since 2015. The company's oils, sprays, lotions – and even water – are available in mainstream grocery and health stores. They contain one of the main active ingredients of cannabis – cannabidiol, or CBD, which the company says reduces anxiety.

Professional bodybuilder James Hollingshead has been a customer since May. "The biggest thing for me is the psychological aspects of not feeling overwhelmed, feeling somewhat restful and somewhat relaxed despite what’s about to happen and what I'm preparing [for]," he told CGTN.

Love Hemp has seen a sharp increase in sales of its products including oils, which contain eight to 40 percent of CBD. In the last 12 months, they've seen sales of nearly four million US dollars.

Tony Calamita, co-founder and managing director of Love Hemp & CBD Oils UK, said: "We still have some way to go, but the acceptance of cannabis as a normal product and all the negative connotations that come along with it is moving in the right direction and public perception is slowly getting very positive."

THC, the cannabis ingredient associated with euphoria – but also linked to psychosis – is illegal in Britain. But a new government review into medicinal marijuana could change that. It follows the separate cases of two young boys with rare forms of epilepsy who were granted short-term emergency access to cannabis oil containing THC from overseas.

Tony Calamita welcomes the potential easing of rules, saying that "we do believe that some THC in controlled amounts with the supporting studies can have even great health benefits, so we would really at some point in the future be able to incorporate a controlled amount of [it] into certain products."

A leading conservative campaign group, the TaxPayers' Alliance (TPA), has joined other think tanks and politicians in calling for full legalization of medicinal and recreational uses of cannabis – for fiscal reasons.

TPA's Grassroots Campaign Manager Harry Fone told CGTN: "The country could save around 890 million pounds per year – that's roughly around 1.2-1.3 billion dollars. This is in terms of costs in policing that would be saved… And the policing costs are probably one of the major factors, at least 200 million pounds or 300 million dollars a year. So there are huge savings to be made here for the government and, subsequently, taxpayers."

Many experts welcome the relaxation of medicinal cannabis laws, but warn that full legalization along the lines of the US state of Colorado could have negative health implications.

Sir Robin Murray, professor of Psychiatric Research at King's College London, told CGTN: "They have legalized cannabis as in the Wild West, which is where they are. Anything goes, and what has happened is the potency has increased…In Colorado you can get 60, 80, 99 percent THC. So this is a bit like comparing a shandy or lager with the strongest vodka or whisky."

Canada recently became the second country in the world after Uruguay to legalize cannabis. With UK public attitudes shifting, it may not be long before British law catches up.