Aspartame is derived from phenylinaline, an amino acid, that is able to cross the blood brain barrier. It directly effects the brain, much in the same way as many drugs do. It enhances dopamine, norepinephrine, and adrenaline, and It is very addicting, talk to any one who has tried to quit drinking diet pop. You will experience withdrawals, listlessness, headache, and so forth. Cocaine enhances the same neurotransmitters. For those who are addicted to this artificial sweetner, and trying to go "cold turkey", a useful tidbit would be to increase Tyrosine rich foods, such as almonds, avocados, bannanas, dairy, and pumpkin seeds, or take a Tyrosine supplement. Tyrosine activates the same neurotransmitters, to lessen the withdrawals. More than likely lose weight, as it also activates thyroid hormone, and increases metabolism.
Recent research has stated that artificle sweetners such as aspartame, actually feed fat cells, therefor, it becomes a vicious circle, and a broken promise to those trying to lose weight. Your addicted, and gaining weight. How sad, its to keep you hooked, and buying it. Coca Cola, back in the day, actually had cocaine in it, to keep you drinking it, and addicted. Hence the name Coca Cola.
I am actually allergic to all artifical sweetners, Nutra sweet, and Equal all contain the same thing. Throat, and tongue swell. If you have PKU disease, definitely avoid all of them. Read labels, there are numerous products that contain these sweeteners, and the derivatives.
The choice is yours.