There are a number of diet sodas that do not contain aspartame. Some possible choices include Hansen's Natural Soda, Diet Rite Soda, and Diet Coke sweetened with Splenda.
Due to health-related concerns surrounding the use of aspartame as an artificial sweetener, several companies have released diet sodas sweetened without aspartame or sugar. Some major brands, such as Coke and Pepsi, have switched to Splenda to sweeten their sugar-free beverages. Other brands, such as Hansen's and Zevia, use safe and healthy natural sweeteners such as stevia. Possible health risks for heavy aspartame users include headaches, memory loss, mood swings and diarrhea.