Hi, a warm welcome to the site. The Food Information Regulations 2014 is the legislation that states that there needs to be labelling on foods which includes information about any additives.
This page of food.gov.uk helps to explain what food additives are
https://www.food.gov.uk/safety-hygiene/food-additives and then a little further down the page how food colours are linked to hyperactivity & E numbers.
From page 68 of the Level 2 Introduction to childcare:
Quote Food Information Regulations (FIR) 2014
Under this general legislation all early yerars settings in the UK that provide food for children must correctly state the ingredients in all food that they prepare. They must also clearly state if any of the ingredients fall into one of the fourteen food categories that are likely to cause allergic reactions. The categories are listed in the legislation and include familiar ingredients, such as nuts and milk, as well as less familiar things like sulphur dioxide, which is used as a preservative. You and your setting must know about these. Keep up to date with details of these requirements by checking www.food.gov.uk
Hth xx
Legislation surrounding food additives
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