Aspartame (NutraSweet or E951) is an artificial sweetener used in many diet soft drinks and other foods.
Stories have been circulating for a number of years that suggest that this product is unsafe and might cause a range of health problems including multiple sclerosis. The theoretical concern is that as the body breaks down aspartame it is converted to methanol and then to formic acid, which can be toxic. However, research has shown that eating or drinking large quantities of foods that contain aspartame causes little change in the levels of methanol or formic acid in the blood.
The Food Standards Agency in the UK, the Food and Drug Administration (FDA) in the USA and the European Commission's Scientific Committee on Food (SCF) have all reviewed the evidence and concluded that aspartame is safe to use at normal levels of consumption, with the exception of those people with the inherited condition phenylketonuria (PKU) who are unable to metabolise the amino acid phenylalanine which is present in aspartame. There has been no published, peer-reviewed research that supports the link between aspartame and MS.