If you look into the history of aspartame, you find a story of government corruption. Initially it was banned, but then it was approved. All the industry-funded studies found no problem with it, but nearly all other studies found a problem with it. People were complaining about headaches caused by consistent aspartame consumption (multiple cans of diet drink per day, stuff like that). So Monsanto funded a study that took people who complained about aspartame headaches, and got them to drink a can of diet drink. None of them reported headaches. In the real world, though, consistent aspartame consumption resulted in occasional headaches. The industry-funded study proved it was harmless, though. Trust the $cience.