How bad are artificial sweeteners?

Growing up as a child there were always two things my mum never let me have: chewing gum and coke. I used to get so excited when I went to a friend's party and we could drink coke. Or when my dad would secretly offer me some gum in the car and say not to tell mum. The reason my mum gave me when I asked why I wasn't allowed them was, 'they are bad foods because they are so full of sugar. You already get enough sugar without eating them.'

As I became a teenager I was able to make my own choices about what to eat and of course I indulged in soft drink, often coke, when out with friends. When I got my driving license I made a habit of buying gum to keep in the car and chew when I drove. My compromise for going against my mum's teachings and staying healthy? I always bought coke zero and sugar-free gum.

Over the years I have heard various stories about the 'crap' put in diet coke and coke zero. 'Diet coke gives you cancer' is a common one. Now as a young adult I don't drink much coke, maybe a 450ml bottle once a month, and I don't chew gum at all. But today just so happened to be one of the rare days I splashed out and bought a coke zero for myself while traveling home from uni. While drinking it I took a look at the label and the ingredients, here they are:

The main sweeteners are Aspartame and Acesulphame-K. I decided to do a little more research to discover if these two sweeteners really deserve their bad reputation, and whether I want drink this stuff.

The first website I visited was:  http://www.thezeromovement.org and they gave an interesting description of the ingredients:

The ingredients (as written in bold) are listed on Australian cans of Coke Zero. Water anyone?

Carbonated water
Colour (150d) - aka "Sulphite Ammonia Caramel"
Food acid 338 - aka "Phosphoric Acid" (Also used for rust removal!)
Food acid 331 - aka "Sodium Citrates" (Also used in photography and as an anticoagulant of blood stored for transfusion!)
Flavour
Sweetener 951 - aka "Asapartame" (According to the US FDA, "the [National Cancer Institute] currently is studying aspartame and other dietary factors as part of a larger study of adult brain cancer." You might want to wait for the results before you drink it. Also, avoid this one if you're moody!)
Sweetener 950 - aka "Acesulfame Potassium" (Looking for reasons to avoid this sweetener? Look no further...)
Preservative 211 - aka "Sodium Benzoate" (Undiluted this stuff isn't too bad... Just don't let it touch your skin!)
Caffeine

This website certainly damns just about everything in a bottle of coke. After googling sweeteners 950 and 951 I found this website http://ehlt.flinders.edu.au/education/DLiT/2006/food%20additives/theyare/avoid.htm which I deemed to be a little more reliable as it an education website. The website claims the following side effects from sweeteners 950 and 951:

Cancer, asthma, MS-like symptoms, headache, hyperactivity, fatigue, anxiety, dizziness, migraine, memory loss, depression, insomnia, irritability, impotence, epilepsy, blindness, diabetes, neuralgia, seizures, brain damage, gastrointestinal upsets

These two websites certainly make a strong case for the dangers involved in consuming the sweeteners in diet coke and coke zero. Though I would have to look at a wider range of sources before finally deciding whether or not to give up sugar-free coke, what I have seen so far worries me. It has certainly spurred me on to become more aware of what's in food and drinks.