Phenylalanine

I have been so cautious since the day I started to check what are in whatever i consume... like thousands of instant things.
Dont judge me, its an instant era, none really have time to do anything manually.

Can you imagine that they put phenylalanine even in (an instant) Curcuma Extract? In Ice lemon tea? Even in some of medicine I am using!

So at first, I was wondering what the F is that thing. I asked some people I know that they know more than I know, none answered me yet.

What to do?
I google.

Great start, it doesnt really sound dangerous as Wordreference says

Phenylalanine : an essential amino acid found in proteins and needed for growth of children and for protein metabolism in children and adults; abundant in milk and eggs; it is normally converted to tyrosine in the human body.

It sounds great!
Phenylalanine is needed for growth of children!
Yet it bothers me that so many things has Phenylalanine on their boxes. Why so?

Sweetpoison answers me,

Phenylalanine is a hidden danger to anyone consuming aspartame. Most consumers don't know that too much Phenylalanine is a neurotoxin and excites the neurons in the brain to the point of cellular death. More...

Now you know what I know.

Your sugarless gums, Monster Munch crisps, sugarless soft drinks (such as Diet Coke),
Equal, NutraSweet etc are something BAD !!!