The daily allowance for a person's sugar intake should be halved to six teaspoons, the World Health Organisation says.
Its draft guidance advises a dramatic drop in sugar consumption to help avoid mounting health problems including obesity and tooth decay.
It proposes to retain its current formal recommendation that no more than 10 per cent of an individual's calories should come from sugar - the equivalent of 12 "level" teaspoons a day for the average adult.
But its draft guidelines say a cut to 5 per cent "would have additional benefits". The lower limit amounts to about six teaspoons.
The WHO move comes amid growing evidence that sugar contributes to a range of chronic diseases and follows calls by scientists for the recommendation to be halved.