This applies more so to good quality lager, some of the more well known lagers loose a lot of goodness because of the accelerated brewing through the use of chemicals. I believe in the days London's water was completely unsanitary and sewage drainage would regularly contaminate water sources it was common for people in certain areas to drink beer instead water, in fact some neighbourhoods close to breweries showed less plague related deaths, as the beer was more higienic due to the fermentation process. Beer loves you, and you should love it back.