The Unit Measuring System


The strength of alcohol in various drinks varies enormously. To help people to understand the amount of alcohol they consume the unit measuring system was devised. The number of units in pre-packed drinks is now often printed on the label.

One UK unit is 10ml or eight grams of pure alcohol (also called ethanol).

To work out the units in a drink:
1) take the volume of the drink and multiply it by its alcohol by volume (abv)
2) divide by 1000.

So for a two litre bottle of cider at 9% abv
(2000 (volume) x 9 (abv))/1000 =18 units

Approximate limits are listed below:

 

Daily
Spread over the week
Harmful
Dependency
Men
3 or 4
21
50
100–150
Women
2 or 3
14
35
80–120

Wearing Off


On average it takes a healthy person who is not a heavy drinker roughly one hour to get rid of one unit of alcohol – estimates vary on how long it takes the liver to start breaking it down from 20 minute to one hour.

Guidance on Sensible Drinking

In arriving at specific advice on sensible drinking we have taken account of the following factors:
• setting daily benchmarks can help individuals to decide how much to drink on single occasions and to avoid excessive drinking with its attendant health and social risks.
• drinking alcohol confers a significant health benefit in terms of reduced CHD mortality and morbidity on men aged over 40 and postmenopausal women. In terms of all cause mortality and morbidity the benefit can be largely gained by drinking as little as 1 unit a day on a regular basis. Consumption above 2 units a day does not confer any major additional health benefit.

• men who drink more than 3 to 4 units a day run an increasingly significant risk of illness and death from a number of conditions, including haemorrhagic stroke, some cancers, accidents and hypertension.

• for women there are a number of additional factors to be taken into account: differences in average weight and tissue density from men and the effects of the menopause, as well as the patterns of female mortality and the possible risk of breast cancer. These factors point to setting a lower overall level than for men.
Women who drink more than 2 to 3 units a day run an increasingly significant risk of illness and death from a number of conditions, including haemorrhagic stroke, some cancers, accidents and hypertension.
Sensible Drinking The Report of an Inter-Departmental Working Group, Department of Health, December 1995