Aspartame is an Excitotoxin. I recommend exactly 0 grams daily.
Like MSG, it stimulates the Nervous System...
In your Pancreas this causes insulin release, which causes a drop in blood sugar, which causes the hungries...
This is one of the reasons that people who Drink Diet Soda are show to eat more food.
Aspartame may cross the blood brain barrier and damage brain cells by excitatory neurotoxicity.
Can cause an immune response causing blood vessels to become leaky, thus resulting in Systemic Inflammation. If you read here often, you know Inflammation is tied to most diseases, weight gain etc etc.
Cockblocks Leptin. Completely shuts it down. If your brain and gut cannot communicate, it makes health ridiculously difficult.
Phosphoric Acid... do you know what this stuff is? Its used for Rust removal, it DESTROYS Bones...even yours.
In short... ditch it. In the trash, and Dont look back.
If you need the caffeine, go for a low fluoride tea or some coffee. You'll feel look and perform better.
More Reading:
Hannah Gardener, Sc.D., an epidemiologist with the Miller School of Medicine and project leader on the diet drink study, presented the findings at the Los Angeles Convention Center. Dr. Gardener detailed the project, which tracked more than 2,500 Manhattan (New York City) residents for approximately a decade. Ongoing examinations tracked participants' ages, daily calorie totals, exercise, alcohol use, smoking habits, blood pressure, cholesterol levels, and more.
Statistically speaking, those subjects who consumed diet sodas daily experienced a 61 percent higher risk of stroke and heart attack than those who abstained from the low-calorie carbonated beverages. No elevated risks of vascular problems were noted among daily drinkers of regular (sugared) sodas.
The ingredients in aspartame include aspartic acid, phenylalanine, and methyl alcohol. Do you remember from high school science that methyl alcohol is poisonous to the body? When methyl alcohol breaks down in high temperatures it turns into FORMALDEHYDE and DKP (diketopiprazine). These are two highly toxic chemicals that adversely affect the nervous system.
The Dangers of Aspartame (Artificial Sweeteners Sugarfree Diet Coke Zero No Sugar Added E951)
http://youtu.be/pvFRLIjOLOU
Edit: I wanted to add, Artificial Sugars do bad things to your Gut Bacteria as well. Which is an entire other thread of why they are bad.
Edit#2: also want to recommend

Excitotoxins: The Taste that Kills by Russell Blaylock