BUT! in a nutshell, aspartame prevents the body to burn carbohydrates and can cause you to become depressed. If you are interested in the neurological explanation, I entreat you to read further my fellow geeks!
First off, it is important to recognize that neurons synthesize serotonin from an amino acid found in proteins called tryptophan. aspartame contains high levels of the chemical phenylalanine, which competes with trypophan for entry to the brain. There are only a certain number of "spots" in which amino acids can cross the blood brain barrier to synthesize serotonin, and thus too much phenylalanine will prevent trypophan from entering which in turn will impair the brains ability too synthesize serotonin. And thus, depression ensues!
I just thought this was intriguing and desired to share with my fellow "ana sisterhood". HAHAHAH.