Anthropologist Alan Macfarlane of Cambridge University has an intriguing theory about the origins of the Industrial Revolution. You can hear about it in the course of these lectures on population growth.
But what does that have to do with tea?
Macfarlane notes that one of the big puzzles for modern demographers is why the population of England [...]
I heard about this a while back (maybe being in UK we dwell on these things more...); it makes some sense, although could be synchronicity as much as fact. Another factor the tea-drinking brought was, not only that people could survive/avoid stomach ailments through the boiling of water, but the very 'healthy' properties of tea itself allowed for a fitter workforce - ie you could cram more people into factories in close proximities with lesser risk of one worker's cold/flu (potentially fatal!) spreading across the whole workforce. Tea upped the worker's resistance to infections, if not their resistance to exploitation...! Tea - the capitalist beverage.