Ever a skeptic, I have read the links attached by others describing the dangers of artificial sweeteners, but none list quantities required to induce the negative symptoms as compared to quantities actually found in the artificial sweeteners. I've read accounts proclaiming that aspartame breaks down into methanol and formaldehyde in the body, and then citing the dangers of these chemicals in the body. Again, no mention is made of amounts. As per the Discover article below, "Both methanol and formaldehyde are toxic in high doses, but a person would have to drink 600 cans of diet soda to get as much of either substance as is contained in a single orange."
I also remember reading the origins of the "sweet-n-low causes cancer in lab animals" study, prompting the warning to be placed on the product. The study was conducted on rats, which have metabolic differences from humans, resulting in bladder tumor formation in rats when given continual high doses of saccharin but no similar effect when the same amount (as a percentage of body mass) was given to primates. In any case, aspartame "has been studied more than any other substance in FDA history, yet it has consistently been declared safe" (again, in the Discover article).
Yes, I can agree with the basic stipulation that there are possible risks attached to consuming artificially made food additives, but I believe there is much more myth than truth to most claims. Artificial sweeteners are over a hundred times sweeter than sugar, thus the amount used in a product is less than 1% of the amount of sugar needed in the "non-diet" version.
I've read about concerns for PKU, an inherited metabolic disorder which is affected by the phenylalanine present in artificial sweeteners. Yes, this is a serious disorder, which is caused by the individuals being unable to metabolize phenylalanine properly, and causing amino acid build-up in the brain, eventually causing severe mental retardation. What isn't mentioned when PKU is referenced is that infants are checked for this at birth and it is the symptoms, not the disorder, which develop over time with exposure to phenylalanine in the diet. One website recommended individuals get tested for this disease if they suspect to be having adverse reactions to artificial sweeteners. If an adult was not diagnosed as an infant with PKU but had the disorder and consumed a non-restricted diet, that adult, if still alive, would be so severely mentally disabled that reading an website would be an impossibility (as would speaking, moving, possibly breathing without mechanical assistance...).
One thing I notice when searching the web for "artificial sweetener danger" is that the sites promoting the dangers are often also promoting the sale of something in the "natural living" genre: books, supplements, etc. This seems to me too much like a scare tactic, directing readers to "salvation" through the products/philosophies promoted by these websites. Those that aren't seem to be merely echoing the exact same "studies" consisting primarily of anecdotal evidence.
I see a lot of "headaches" listed as symptoms ascribed to consuming artificial sweeteners, usually in the form of diet soda. I'm wondering if it isn't more the caffeine withdrawal and/or sodium causing this.
As an additional note of irony, many of these "natural living" websites speak of the dangers of artificial sweeteners, despite any scientific studies backing -- and many refuting -- their claims, then go on to list recommended supplements (which, as designated, avoid FDA testing which artificial sweeteners have overwhelmingly passed) with dubious claims based on anecdotal evidence.
Aspartame controversy - Wikipedia, the free encyclopedia
snopes.com: Aspartame -- Sweet Poison?
Saccharin - Wikipedia, the free encyclopedia
C&EN: WHAT'S THAT STUFF? ARTIFICIAL SWEETENERS
The Chemistry of . . . Artificial Sweeteners | Senses | DISCOVER Magazine