Restaurants and other businesses need to tell customers if their food could trigger allergies or raise other health concerns in a new EU labeling rule taking effect on Saturday.
"Key content information will now be more clearly marked on labels, helping people make informed choices on the food they buy," Health and Food Safety Commissioner Vytenis Andriukaitis said in a statement.
The labeling, which has been three years in the making, applies to food served in restaurants, cafes and bakeries as well as pre-packaged products, according to the European Commission, the EU's executive arm.
It calls for a "clearer and harmonized presentation" of 14 allergens including soy, nuts, gluten or lactose in the list of ingredients for pre-packed foods.
Allergen information must also be given for food that is not pre-packed.
The rules also require clear information about the origin of fresh meat from pigs, sheep, goats and poultry as well as on the vegetable origin of refined oils and fats.
Lists of ingredients must include engineered nanomaterials; tiny materials that may be used in chocolate desserts, pork products or soups which are suspected of harming human health.
However, mandatory nutritional labeling for processed food will only take effect from December 13, 2016.
The Commission said it had been working with businesses to ensure the new rules will be properly implemented.
The rules were adopted by the European Parliament and 28 European Union member states in 2011.