...is the name for an artificial, non-saccharide sweetener, aspartyl-phenylalanine-1-methyl ester; i.e., a methyl ester of the dipeptide of the amino acids aspartic acid and phenylalanine.

This sweetener is marketed under a number of trademark names, including Tropicana Slim, Equal, NutraSweet, and Canderel, and is an ingredient of approximately 6,000 consumer foods and beverages sold worldwide. It is commonly used in diet soft drinks, and is often provided as a table condiment. It is also used in some brands of chewable vitamin supplements and common in many sugar-free chewing gums. However, aspartame is not always suitable for baking because it often breaks down when heated and loses much of its sweetness. In the European Union, it is also known under the E number (additive code) E951. Aspartame is also one of the sugar substitutes used by people with diabetes.
from wikipedia.com


Overall

• Aspartame is safe at current levels of consumption, which remain well below established ADI levels, even among high user sub-populations. No credible evidence was found that aspartame is carcinogenic, neurotoxic or has or any other adverse effects when consumed even at levels many times the established ADI levels.

Specifically:

* Based on results of several long term studies, aspartame does not have carcinogenic or cancer-promoting activity.
* Results of extensive investigation in studies that mimic human exposure do not show any evidence of neurological effects, such as memory and learning problems, of aspartame consumption.
* Overall the weight of the evidence indicates that aspartame has no effect on behavior, cognitive function, neural function or seizures in any of the groups studied.
* Aspartame has not been shown to have adverse effects on reproductive activity or lactation.
* Studies conclude that aspartame is safe for use by diabetics and may aid diabetics in adhering to a sugar-free diet.
* There is no evidence to support an association between aspartame consumption and obesity. On the contrary, when used in multidisciplinary weight control programs, aspartame may actually aid in long-term weight control.
* The studies provide no evidence to support an association between aspartame and brain or hematopoietic tumor development.
from science daily