Units are a clever way to help you know just how strong your drink is.
One unit of alcohol is 10 ml or 8g of pure alcohol. This equals a third of a pint of beer.
Alcoholic drinks are made by fermenting and distilling natural starch and sugar.
Beer can contain lots of calories. For instance, a pint of larger with 4% ABV can contain 180 calories, similar to a slice of pizza.
Two bottles of beer can contain as many calories as a sirloin steak.
Lager like any kind of alcohol, can stimulate the appetite and make calorific post-pub food like kebab and chips look more appealing.
How much is too much?
The UK Chief Officer updated the alcohol unit guidelines in January 2016. Advice is that both men and women should not regularly drink more than 14 units a week.
Find out more about the new CMOs' low drinking guidelines here.