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Food additive intolerance


Food additives are substances that are added to foods for a particular function, such as to colour or preserve them.

In some people these additives may cause an allergic reaction, or they may cause hyperactivity in children. People who react to additives normally have asthma or other allergies already.

Reactions to additives usually bring on an asthma attack or cause nettle rash (hives). Sulphites, benzoates and tartrazine are all types of additives that can cause these symptoms in some people.

Additives that can cause allergic reactions


Sulphur dioxide (E220) and other sulphites (E221, E222, E223, E224, E226, E227 and E228) are used as preservatives in a wide range of foods, especially soft drinks, sausages, burgers and dried fruit and vegetables.

Sulphur dioxide is produced naturally when wine and beer are made. It is often added to wine to stop it from continuing to ferment in the bottle. Usually, most of the 'head space' in a bottle of wine (the part of the bottle not filled with wine) is sulphur dioxide.

Anyone who has asthma may react to inhaling sulphur dioxide. A few people with asthma have had an attack after drinking acidic drinks containing sulphites, but this is not thought to be very common.

Food labelling rules require pre-packed food sold in the UK, and the rest of the European Union, to show clearly on the label if it contains sulphur dioxide or sulphites at levels above 10mg per kg or per litre. Bear in mind that there could still be foods on the shelves that were produced before this law was introduced (November 2005).


Benzoic acid (E210) and other benzoates (E211, E212, E213, E214, E215, E218 and E219) are used as food preservatives to prevent yeasts and moulds from growing, most commonly in soft drinks. They occur naturally in fruit and honey.

Benzoates could make the symptoms of asthma and eczema worse in children who already have these conditions.


Tartrazine (E102) is a yellow colour used in a range of foods, including soft drinks, sweets and sauces.

Studies have shown that eating foods or drinks containing tartrazine can cause nettle rash (hives), dermatitis (an allergic skin condition), asthma or rhinitis (runny nose) in a very small number of people.

The use of tartrazine has decreased in recent years.

Additives that can cause hyperactivity

If your child shows signs of hyperactivity or attention deficit hyperactivity disorder (see below for definitions of these), try to avoid giving them the following artificial colours as this might improve their behaviour:

  • sunset yellow (E110)
  • quinoline yellow (E104)
  • carmoisine (E122)
  • allura red (E129)
  • tartrazine (E102)
  • ponceau 4R (E124)

These colours are used in a number of foods, including soft drinks, sweets, cakes and ice cream.

When colours are used in food, they must be declared in the list of ingredients as 'colour', plus either their name or E number. If any of six colours listed above are in food or drink, the food label must also have a specific warning saying that the colour 'may have an adverse effect on activity and attention in children'.

Food and drink produced before July 20 2010 can continue to be sold, so it might take time for the newly labelled products to appear on shop shelves.

You can avoid certain additives by checking the label. If you buy any foods that are sold without packaging you will need to check with the manufacturer or with the person who is selling the product.

The Food Standards Agency is encouraging manufacturers to work towards finding alternatives to these colours. Some manufacturers and retailers have already taken action to remove them.

What is the difference between hyperactivity and ADHD?

In the context of this advice, hyperactivity is when a child is over-active, cannot concentrate and acts on sudden wishes without thinking about alternatives.

There is no single test for diagnosing hyperactivity. Experts think it affects 2 to 5% of children in the UK.

It is important to remember that hyperactivity is also associated with many other factors in addition to additives. These include premature birth, genetics and upbringing.

ADHD is more than just hyperactive behaviour. It is linked to a specific pattern of behaviour, including reduced attention span and difficulties concentrating to the extent that they affect the child’s ability to learn and function at home and at school. Children with ADHD often have learning difficulties and behavioural problems. See  ADHD for more information.

How was the advice on colours agreed?

This advice on food additives and hyperactivity was issued after being evaluated by the independent Committee on Toxicity and the European Food Safety Authority (EFSA) of research commissioned by the Agency.

All food additives must go through rigorous safety assessment and approval procedures, and must comply with European Union (EU) legislation. EFSA is reviewing the safety of all food colours that are approved for use in the European Union.

What are E numbers?

All food additives, whether they are natural or artificial, must go through rigorous safety assessment and approval procedures, and must comply with European Union (EU) legislation. They are only allowed to be used if experts decide that they are necessary and safe.

If a food additive has an E number, this shows it has passed safety tests and been approved for use throughout the European Union.

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