You know, I have often wondered about the odd measurement of alcohol strength that the UK uses - aka "the unit" - because it is so obscure. For me, I would like to see the number of ml of pure alcohol listed on every bottle. Wouldn't that be the easiest thing to do? Instead, we in Canada get percentage meaning we have to do simple math. Such a task can leave a simple soul like me lost.
But the British take it one step of abstraction further with this "unit" stuff. I have in front of me a 500 ml bottle of the overly-named "Duchy Originals from Waitrose Organic Old Ruby Ale 1905" and see two diagrams. One has a glass with "1.4 UK units" in the drawing of the glass and 284 ml below it. The other has "2.5 UK units" super imposed on a silhouette of a bottle. I don't know what the 284 ml exactly means but I presume it is a half pint. So, it suggests that I need to consume 500 ml bottles of beer in 284 ml portions. Silly advice #1. These measures each seem to be two "units" of procurement and consumption. But neither are a whole "unit" in the sense of the health warning, if only because each diagram displays a number with a decimal. So what is this sort of "unit"?
Pete Brown to the rescue. He sent me a set of the new paperback editions of his three books on beer. I plan to give the autographed set as a gift in the 2010 Christmas photo contest but, as Man Walks Into A Pub is now in its second edition with new material added (and a far less ugly cover) since I reviewed it back in 2003 - actually before this blog separated off of the mothership - MWIAP will be presented with a dog-eared gift. First passage I read? It's about "units" at page 392:
The invention of safe limits for alcohol unit consumption was one such "unverified fact". A unit is ten millimetres of ethyl alcohol, the amount the average healthy adult can break down in an hour. In 1987 the Health Education Authority and Alcohol Concern agreed that units were a good way of teaching people about alcohol consumption, and recommended that men should drink no more than twenty-one units a week, and women no more than fourteen. Above that level, they claimed, the risk of alcohol-related harm increased exponentially. What they didn't see fit to mention was that only five years earlier, the Royal College of Physicians and the British Medical Journal had been advising that the safe limit for men was fifty-one units a week.. There was no new research to back up the reduction to twenty-one units five years later, and not reason for doing so.
What I find extraordinary about this passage is not the shift in official advice during the 1980s but the confirmation that a unit is "the amount the average healthy adult can break down in an hour." Because it gets me wondering what that means in terms of comparison to drunk driving standards. Here in Canada was happily have a dual law. 
You can be, generally speaking, convicted for driving while intoxicated or convicted for blowing into a breathalyzer and being found to have over 0.08 mg (I think "mg") of alcohol per "X" litres of blood. So, on the one hand, you can be intoxicated and be under the scientific test if you have low tolerance. You can also be not intoxicated but have too much booze in you to drive if you have high tolerance. As a public standard for safe driving, it works as far as I am concerned. I am, after all, a Beer Blogger Against Drunk Driving.
The thing is, I am not sure that you come anywhere near those limits by sticking to "the amount the average healthy adult can break down in an hour" and I thought for some reason you would have to. Let's review. The bottle of "1905" says as part of the UK warning that it is recommended that I have no more than 4 "units" - or one litre of 5% beer - a day. Two bottles of "1905". According to this blood alcohol calculator, that would give a 200 lb man an level of 0.047 after one hour since the first drink. Me, I am bigger so the level is lower. Please check my math. Have I got this right?
Now, I am quite a happy taxi hirer and have absolutely no issue with grabbing a cab at any occasion. I would have to sit a bit longer for two pints of 5% to be comfortable driving and, still, probably would not. Personal decision. But I would in no way think that I have done myself a long term physical injury by having a third pint over a span of two hours. Yet that is what the UK standard of "units" suggests. I think I might feel dragged out if I did that every day Monday to Friday. I might even start to tweet too much as we all are witnessing from the Great American Beer Festival right now. But even if I did have three pints for five days in a row, I am still well under the pre-1987 recommended level for weekly intake and would feel my best again after a couple of days on black tea and cucumber sandwiches. Check my math. Is that correct?
What does this tell us? First, that the medical advice for, what shall we call it, "drinking and living" presents a significantly stricter standard than the criminal one for "drinking and driving." Second, it tells me that I want to know much more about the difference between 20 and 51 units a week. What exactly does it mean? Is the liver so fragile that it cannot take a pace of alcohol consumption that is greater than "the amount the average healthy adult can break down in an hour"? How is it that the body is born with a capacity to break down a naturally occurring substance like ethyl alcohol and yet it is prone to being damaged by it at a level of consumption far lower than the level that causes the minimum level of motor control disfunction requiring legal intervention for the safety of others?
Third, it tells me that you need to get the second edition of Pete's first book even if you bought the first one seven years ago. It's full of handy stuff that gets your unaddled brain going.
