Aspartic Acid

• Aspartic acid, or aspartate, makes up about 40 percent of aspartame. In the brain, aspartate acts as a neurotransmitter, helping information get from one neuron to another. An excess amount of aspartate in the brain releases free radicals and, in turn, kills the neurons by allowing an excess of calcium to be absorbed. Multiple sclerosis, epilepsy, dementia and Parkinson's disease are only a few of the chronic illnesses linked to excessive amounts of aspartate over an extended period of time. The FDA has reported nausea, vision and sleeping problems, migraines and more as side effects of too much aspartate in your system.
  
  

Phenylalanine

• Phenylalanine, an amino acid, makes up about 50 percent of aspartame. Phenylalanine raises the blood phenylalanine levels, which can decrease serotonin, and can lead to depression, seizures and even schizophrenia.
  
  

Methanol

• Methanol, also known as wood alcohol, makes up the remaining 10 percent of aspartame. Methanol breaks down into formic acid and formaldehyde in the body. Formaldehyde is highly poisonous and has side effects such as headaches, vertigo and neuritis. The EPA recommends a daily limit of 7.8 mg a day of methanol, which equals about a 4-oz. sip of an aspartame-sweetened beverage.
  
  

Diketopiperazine (DKP)

• When aspartame is metabolized, your body produces DKP, which is purported to have brain-tumor causing effects. Uterine polyps and increased cholesterol levels have been linked to DKP as well.
  
  

Considerations

• More than 75 percent of negative food reactions, including seizures and even death, are said to be attributed to foods containing aspartame. With all of the potentially negative side effects out there---such as seizures, vomiting, nausea and birth defects---you may want to limit the amount of aspartame in your diet. Consult with your physician if you experience any of the symptoms mentioned, and be honest with him or her about the amount of aspartame in your diet. There have been many cases of people suffering side effects upon removing aspartame from their diet, but those side effects are less severe than the potential illnesses that aspartame has been linked to.