There's conflicting evidence regarding the safety of aspartame, a common chemical sweetener used in diet soda and other low-cal foods, but some people report headaches or generally feeling unwell after ingesting anything containing the chemical. To make life easier for everyone, this is one instance where you may want to follow the "better safe than sorry" principle. That's because a University of Liverpool test-tube study found that when mixed with a common food color ingredient, aspartame actually became toxic to brain cells.
Aspartame is used in many diet sodas, and researchers are finding that drinking two diet sodas a day can lead to a 500 percent greater increase in waist size. Furthermore, animal studies suggest that aspartame actually increases blood glucose levels similarly to sugar, which could explain the association between diet soda and diabetes.
