aspartame is an artificial, non-saccharide sweetener used as a sugar substitute in some foods and beverages. in the european union, it is codified as E951. aspartame is a methyl ester of the aspartic acid/phenylalanine dipeptide.
I know Cola light/zero uses an artificial sweetener that is considered unhealthy; probably it's aspartame but I didn't control. I'm honestly not surprised, I just find such things a crime. For the sake of money things are put in food and drinks that are slightly to very unhealthy; and aspartame isn't the only one. I know that many numbers of E's are not so good, or should be avoided as much as possible. Though you will never avoid every single thing they put in food, there are too many things in too many articles.