Interviewed* on BBC Radio 4’s “Today” programme, Shadow Health Secretary, Andrew Lansley made a compelling argument for replacing “units” with centilitres.  They are of course exactly the same thing, but unless drinkers actually know that a “unit” is a centilitre, they are unable to relate the “alcohol by volume” (ABV – also indicated on the bottle or tin) to the volume they are drinking (indicated in litres – except in the case of draught beer and cider, but see below).  The use of “units” thus has the perverse effect of obscuring the amount of alcohol that people are drinking.

So for once a politician is ahead of the health professionals, although he did not add that no labelling scheme will be fully effective unless it is mandatory.   According to the BBC website report,  Alcohol Concern were “lukewarm” about the proposal, commenting that “many people were beginning to get a grasp on units”.  [Perhaps if "many people" knew what a "unit" was, they might get an even better grasp].

However, Mr Lansley did not venture into the vexed question of pints of draught beer.  Herein probably lies the reason why many health professionals are unenthusiastic about calling a centilitre a centilitre.  Draught beer and cider are still measured exclusively in pints, and unless you know that a pint is 568 ml, it is no help to know that a “unit” is a centilitre, as you can’t multiply the ABV by the quantity to calculate the number of centilitres.  So, according to this argument, you might as well stick with obscure “units”.

The obvious answer is to bring draught beer and cider into line with all other alcoholic drinks, both draught and bottled/canned.  As a first step, as we have recently argued on this blog, metric quantities of draught beer and cider should be permitted on a voluntary basis in pubs and restaurants that wish to offer them.  If drinks were then also properly labelled, nobody would have any excuse for being unaware of what they were drinking.

In summary, therefore, labelling of alcoholic drinks – both bottled/canned and draught – should be mandatory, and should include:

• Statement of quantity contained or dispensed (in metric units)
• “Alcohol by volume” in percentages
• The quantity (in centilitres) of pure alcohol in the container or in the quantity dispensed

* The interview can be heard on the BBC Radio 4’s “Listen Again”.  It comes at about 07:12 on Wednesday, 13 January.  Or try this link.