Best-selling burgers and drinks popular with children at McDonald's restaurants are loaded with controversial chemicals, including some known to cause behavioural problems.
Analysis by The Independent reveals that Britain's biggest burger company pumps a total of 78 different artificial additives into its food on 578 separate occasions, an average of seven E-numbers per product. Although McDonald's emphasises its burgers are 100 per cent beef, the buns, cheese and sauces that go with them are high in E-numbers.
The Big Mac has 18 separate additives and a cheeseburger 17 separate additives, while a chocolate milkshake has eight different chemicals.
Additives are present in almost everything on the menu, including the grilled chicken and salads.
Health campaigners claim that certain E-numbers can cause side effects such as headaches and wheezing among some consumers.
At McDonald's, there is reason for specific concern because its Big Mac, cheeseburger and quarter pounder with cheese contain a preservative found to worsen hyperactivity in children. Artificial colours in several branded deserts and soft drinks sold at the company's 1,250 branches are also blamed for causing the problem.
After being made aware of the high levels of controversial additives, campaigners urgently called on McDonald's to make its food less reliant on chemicals. However, The Independent's research suggests that McDonald's aim of reducing E-numbers in response to public concern has not been successful. The firm's use of additives seems to have increased rather than decreased during the past year.
In the past four years, McDonald's has been seeking to ward off criticism that it encourages obesity and build a reputation for healthy eating by introducing salads and mineral water. Customers of the chain are told that its menu is based on staple foods such as meat, fish potatoes, eggs, milk and grain. They are assured: "The freshest ingredients are used..."
McDonald's British headquarters in East Finchley, London, refuses to disclose the number of additives it uses, to customers or to the media. But by analysing the 2,000 ingredients on the company's nutrition web pages, The Independent has established that McDonald's uses a range of 78 different additives on 578 separate occasions. Only 13 of its products such as tea, fruit bag and carrot sticks do not contain E-numbers.
Processed cheese squares contain acidicity regulators. Bacon comes with sodium ascorbate and the preservative sodiumnitrate, which is put in fertilisers and explosives.
Researchers at Southampton University have found that children who ingest certain additives are more likely to be over-active, impulsive and unable to concentrate. Four of seven E-numbers highlighted by the researchers are on the menu at McDonald's: sunset yellow (E110), quinoline yellow (E104), ponceau 4R (E124) and sodium benzoate (E211).
In a statement, McDonald's, which made global profit of 3.5bn in 2006, said it was conducting trials to remove sodium benzoate from its burgers, and added that a pickle was the only McDonald's own brand item with a Southampton additive. The company added it was in discussion with suppliers to reduce additives "where possible".
"We are continuing to work hard to reduce and in some cases remove completely the need for artificial colours and preservatives in our food," the company said.
On its website, McDonald's nutritionist assures customers that it is company policy not to use any artificial colours or benzoates in new products. But when The Independent first monitored use of E-numbers in September 2007, the total number used was 568. In October 2007, the date the ingredients list was updated on the website, the number had risen to 578.
Richard Watts, head of the Children's Food Campaign at the food group Sustain said: "We are very concerned that about the heavy use of additives in McDonald's especially the ones identified as harmful to health in the Southampton study." But, he said, E-numbers were "part of the business model" for processed food and would be hard to remove.
Check which sweets and other foods contain additives linked to hyperactivity at www.actiononadditives.com.