It has long been known too much sugar rots your teeth and too many cakes pile on the kilos but many of us are ignorant about how much sugar we are consuming.
Hidden sugars in food products are being revealed as a major driver in the obesity epidemic.
In WA, 66 per cent of adults and 25 per cent of 12 to 17-year-olds are overweight.
A tablespoon of barbecue sauce can contain up to three teaspoons of sugar, half the daily sugar intake to be recommended in new World Health Organisation guidelines.
A pot of low-fat fruit yoghurt could have more than eight teaspoons of sugar because manufacturers take away the fat to appeal to consumers, only to replace it with sugar.
WA's Live Lighter campaign, launched yesterday, urges action on the WHO's proposed guidelines to cut sugar consumption.
Last week, the WHO proposed retaining its current formal recommendation that no more than 10 per cent of a person's calories should come from sugar - the equivalent of 12 level teaspoons a day.
Its draft guidelines add that a further reduction to 5 per cent - about six teaspoons a day - "would have additional benefits".
The WHO's proposals, open for public consultation until March 31, have sparked debate about sugar and its impact on obesity.
WA Department of Health nutrition policy adviser Christina Pollard said dietary advice had long warned against adding sugar to drinks and meals but the advent of processed foods over the past 30 years brought the problem of hidden sugars.
WA Heath Foundation chief executive Maurice Swanson said it was once thought that excess fat was inert, not harmful and was like the body having energy "in the bank".
But now it was known that fat altered the level of some hormones, increased the risk of certain cancers, made cells more resistant to insulin and caused higher "bad" cholesterol levels.