A new law is being brought in to protect people with food allergies.
It's called 'Natasha's Law' and it will mean food businesses will have to include full ingredients labelling on pre-packaged food.
It has been introduced because of the death of a teenager called Natasha Ednan-Laperpouse who died after having an allergic reaction to a baguette.
She was just 15 when she collapsed on a flight from London to Nice on 17 July 2016. She had eaten a baguette that she bought from Pret a Manger.
Millions of people in the UK have a food allergy. It is when the body's immune system reacts unusually to certain foods.
The baguette Natasha bought from Pret a Manger contained an ingredient called sesame - something to which she was extremely allergic.
Sesame was not listed on the packet and a big investigation into Natasha's death found that the labelling wasn't adequate.
Pret a Manger have now changed their labelling rules, but under current rules for items made in store, it is sufficient for general allergen warnings to be posted around the shop, instead of on the individual packaging for items.
The new law, which will apply to packaging in England and Northern Ireland, is set to come into force by the summer of 2021.
Businesses will be given two years to adapt to the changes.
Environment Secretary Michael Gove - the government minister in charge of food standards - said: "These changes will make food labels clear and consistent and give the country's two million food allergy sufferers confidence in making safe food choices."