How to Read a Nutrition Label in 20 Seconds

The front of a food package is advertising. "Natural," "wholesome," "source of protein," "made with real fruit" — these are marketing claims with almost no regulatory teeth, and the products carrying them are frequently worse than the ones that don't.

Turn it over. The back is where the law lives.

Step 1: Check the serving size first

Everything on the panel refers to a serving, and manufacturers choose that serving. A bag of crisps that seems to contain 150 calories may contain 2.5 servings. A bottle of juice may be 2. Look at the serving size, then look at how much of the packet you are realistically going to eat, and do the multiplication before you read anything else.

Step 2: Fibre and protein — the two numbers to want high

• Fibre: a good rule for anything grain-based is at least 3 g per 100 g; for bread and cereal, aim higher.
• Protein: useful mostly for judging whether a snack will actually hold you until the next meal.

Step 3: Added sugar, and the names it hides behind

Most labels now separate "total sugars" from "added sugars" — use the second number. The sugar in a plain yoghurt or a piece of fruit is not the target; the sugar tipped into a sauce is.

In the ingredient list, sugar appears under at least forty aliases. Common ones: glucose-fructose syrup, high-fructose corn syrup, invert sugar, dextrose, maltose, maltodextrin, rice syrup, agave nectar, fruit juice concentrate, molasses, evaporated cane juice. A manufacturer can use three of them in small quantities so that none appears near the top of the list, even though together they are the main event.

Step 4: Salt, and the number people misread

The daily target is around 6 g of salt (about 2.3 g of sodium). Watch the units: sodium and salt are not the same number, and labels vary. Salt = sodium × 2.5. A label showing 1 g of sodium per serving is showing you 2.5 g of salt — nearly half your day in one portion.

The biggest sources are rarely the salt cellar. They are bread, sauces, processed meat, soup and ready meals.

The claims to distrust

• "Low fat" — frequently means sugar was added to replace the flavour.
• "No added sugar" — may still be full of concentrated fruit juice, which is sugar wearing a hat.
• "Multigrain" — means several grains, not whole ones. Look for "wholegrain" or "wholemeal" as the first ingredient.
• "Natural" — in most jurisdictions, means essentially nothing.
• "Fortified with vitamins" — a sugary cereal with vitamins sprayed on is still a sugary cereal.