Here, this should clarify things if you're worried about the health risks:

"Margaret Sadler has lived through five monarchs, two World Wars and remembers life before cars and electricity......Turning 105, she said the secret of her longevity was a bottle or two of Guinness a day and "hard work"....

http://news.bbc.co.uk/1/hi/wales/south_east/7433639.stm