The market for cannabis goes well beyond medicine. Over centuries, it has been used to relieve stress, create feelings of well-being and stimulate positive social behaviours.

It is perceived as healthier and more natural than alcohol and tobacco, and will become more readily available socially as it moves into the global commercial mainstream. This is likely to lead to a huge increase in demand for recreational use.

The global food and drink industry in particular is gearing up to meet this:

• Marijuana-infused beverages are seen as a viable alternative to alcohol. Beer sales could lose $2 billion to cannabis in the US alone.

• Coca-Cola and Constellation Brands (Corona) are investing $4 billion, with Heineken and Molson-Coors also entering the market.

• In the UK, Imperial Brands (Imperial Tobacco) has recently invested £7.6 million.