A food that contains or consists of genetically modified (GM) ingredients must say so on the label. However, labelling isn't required for:
small amounts of genetically modified (GM) ingredients that are accidentally present in non-GM food (below 0.9% for GM crop varieties that have been approved for sale and 0.5% for GM varieties that have received a favourable assessment from a European Commission scientific committee but have not yet been formally approved)
food from animals, such as meat, milk, eggs, that have been given GM feed
food produced with help from a GM processing aid, such as chymosin, which is used to make some hard cheeses
Some food manufacturers are labelling their food as ‘GM-free’. However, there is no legally agreed definition in Europe of what this term means. Any food on sale labelled ‘GM-free’ is subject to the general requirements of food law, in particular the Food Safety Act 1990. This Act makes it an offence to describe, by way of labelling or advertising, a food falsely, or in a way likely to mislead as to its nature, substance or quality.