Finance's reputation as an industry of long boozy lunches and drug-fuelled nights out stretches back decades. And despite the emergence of the uber health-conscious worker arriving at the office in their lycra, the City still plays home to its share of regular drinkers and recreational drug takers - most of whom see themselves as a breed apart from the stereotypical addict.

"Look at a rough sleeper with a can of something. That’s the image most people have as having a problem with alcohol," said Laura Morton, operations manager at Square Mile Health. "If that’s your perception, you’re never going to [consider you] have a problem with alcohol until or unless you turn into the vision."