On a label, "sugars'' means the total of what's natural (say from fruit or milk) PLUS what's added. It doesn't tell how much is added sugar.

You can get clues from the ingredient list which by law must include all ingredients in descending order by weight.

Chemically added sugar is called sucrose but other sugars may be added look for names like glucose (also known as dextrose), fructose, maltose or fruit juice concentrate. See where one of these "sugars'' appears on the list of ingredients. The closer it is to the top of the list, the more has been added. Honey too counts towards the total sugar content even though it's viewed as more "natural''.

Often you'll see two or three types of sugar on an ingredient list. For example, in a muesli bar, there can well be sugar but further down you'll find glucose or honey or fruit juice concentrate. These have different uses but it makes the sugar look less prominent a way of disguising the full amount of sugar.

When foods just have added sugar, like soft drink, the sugar content is easy to work out. You know that there's 11 per cent sugar, all of it added.

But when foods carry both natural and added sugar, it gets tricky. Take cereals.

At the low end, there's plain wholegrain cereals like Vita-Brits and Weet-Bix that have no added sugar. On the label, they have a small 2 or 3 per cent sugar which is naturally occurring. No problem.

At the top end are the sugary cereals that you shouldn't be eating for breakfast. These have 30 or 40 per cent sugars (or more) and are all derived from added sugar.

Then there are the ones in between which have a little added sugar (not excessive and it does improve the taste) so you're left wondering. A handy rule of thumb is to look on the label for one that has 15 per cent or less sugars.

Finally cereals with dried fruit (Sultana Bran, Just Right) are tricky as these have natural sugars as well as added. Look for ones with 25 per cent or less. Compare brands and buy the lowest sugar percentage you see.

Catherine Saxelby is a nutritionist and author of Nutrition for Life. Get more healthy eating tips at www.foodwatch.com.au