The first two are amino acids found in our foods, usually accompanied with a dozen or more other amino acids, however as isolates they're toxic. There's methyl alcohol in oranges and other fruits, but accompanied by much more ethyl alcohol, the classic antidote. The most powerful name behind aspartame is Monsanto, the current owner of the NutraSweet trademark. Now the patent has expired, other companies are also producing aspartame. Disturbingly it's been confirmed that some of these companies are using genetic engineering within the manufacturing process.
Supermarkets now have their own brand table top sweeteners containing aspartame.
It is considered that aspartame is a trigger for many health problems and diseases. In 1995 the United States health authorities recognised 92 different symptoms from rashes and behavioural problems through to what campaigners call Aspartame Disease - sometimes misdiagnosed in such conditions as Multiple Sclerosis and Alzheimer's Disease. Stevia is virtually calorie free - estimated to be at least 100 times sweeter than cane sugar. It's derived from a plant found in the Brazilian rain forests. It has natural antibiotic properties which bring natural protection against tooth decay and gum disease.