The ingredients on a product label are displayed in order from the biggest quantity to the smallest. Scan the ingredients list - does it contain mainly things that you recognise as food, or does it sound more like a science experiment? If you see sugar or words ending in -ose close to the beginning of the list, check the sugar content.
Front-of-pack labels can help save time when you're trying to work out what to choose, but they can also be really confusing because different manufacturers have chosen to use different styles. The traffic light system is simplest to understand. Foods are colour coded according to whether they are low, medium or high in fat, salt and sugar. The more red you see on the label, the more likely it is that you should avoid that food. Foods with all green traffic lights are generally healthier, however, they can still be highly processed and that it why it is useful to scan the ingredients list before you make a decision.
Here are a few examples of different types of front of pack labels, and how to understand them:
Sainsbury's uses traffic lights – you can quickly tell whether a food is high, medium or low in calories, fat and sugar by the colour of the label. Green for low, amber for medium, and red for high.
The style used by Tesco is a small panel that tells you the amount of calories, sugar, fat and salt in one serving. Below this, it shows what % of your 'guideline daily amount' this is. It's important to note that the percentages are based on an average adult – not on someone who is trying to lose weight. But you can get a rough idea of whether the food is high in calories, sugar, fat and salt if the percentages are high. The example below is whole wheat pasta – a portion provides 12% of an adult's calories, which is fine as part of a main meal, but the percentages of sugar, fat and salt are relatively low.
Asda and Waitrose
Asda and Waitrose both use a combination of these systems and are probably the easiest to understand overall.