The artificial sweetener aspartame is being removed from Diet Pepsi in the USA, amid consumer concerns about its safety. Aspartame has been controversial since it was first introduced in the 1980s, despite being one of the most studied and tested of food additives. An Italian study in 2005 claimed to have shown that rats given dosages of aspartame equivalent to that consumed by humans may develop tumours. European regulators are not convinced about the findings however – and the US Food & Drug Administration (FDA) says that more than 100 studies support aspartame’s safety. There are no plans to change the ingredients in Pepsi products in the UK.