How diet soda turns to poison.

Earlier this year, 11-year-old Jennifer Cohen, a New Jersey sixth-grader, conducted a class science project proving that aspartame (the artificial sweetener also known as NutraSweet) breaks down into two deadly neurotoxins. This is an edited version of her report

Suppose evidence was presented to you that strongly suggests that the artificial sweetener in diet soft drinks causes brain tumors. What if overwhelming evidence demonstrated that one of the main ingredients in this sweetener could cause the same brain lesions as monosodium glutamate (MSG) causes? And finally, what if it could be proven that these chemicals can aggravate or even help develop many neuro-degenerative brain diseases and abnormal conditions?

Powerful brain toxins are added to our diet foods and drinks to sweeten them and to boost sales. Disguised as "natural flavoring," these chemicals kill brain cells every time we sip diet soft drinks or bite into the low-fat foods that contain them.

The brain uses excitatory amino acids as neurotransmitters. When exposed to these substances, neurons fire impulses so rapidly that they reach a state of extreme exhaustion. After several hours, the neurons suddenly die. Neuroscientists have named this class of chemicals "excitotoxins."

Neuron death increases the likelihood of neurodegenerative brain disease. According to the Food and Drug Administration (FDA), these diseases include Parkinson's disease, ALS, Alzheimer's disease, and various brain and nervous system tumors.

Aspartame Is the Name

In 1965, Searle chemist Jim Schlatter was developing aspartame for another use when he accidentally licked his finger and noticed that the substance was sweet.

Aspartame is in many products, including some that children use, such as diet soda, low-calorie yogurt, vitamins, baked goods, puddings and gum.

Aspartame's ingredients are aspartic acid, phenylalanine and methyl alcohol. Methyl alcohol breaks down in high temperatures and becomes formaldehyde and diketopiperazine (DKP) -- both chemicals are known to cause problems in the nervous' system. Aspartame's shelf life is 262 days at 77 F (25 C).

Aspartame is consumed by more than 100 million people in the US. The FDA gets more complaints about aspartame than any other food or drink. The symptoms of aspartame exposure are a lot like those of multiple sclerosis and Alzheimer's. It has been known to cause headaches, nausea, vision problems, seizures and cancer.

Ever since the FDA approved aspartame in 1985, brain tumors have increased. The television show "60 Minutes" recently aired a report linking the increase in brain cancer to aspartame use.

A Searle study demonstrated that 320 rats fed aspartame daily for one year developed 12 brain tumors, while 120 rats not fed aspartame remained free of tumors.

A University of Wisconsin research team fed rhesus monkeys aspartame every day for one year. After day 200, they developed epileptic seizures. When the aspartame was discontinued, the seizures stopped.

How I Did My Experiment

On January 21, 1997, I bought a new case of Diet Coke from the supermarket. I put seven cans in the refrigerator, seven cans in my room (about 69 degrees) and seven cans in a Boekel incubator (80 Watts, 120 AC volts, 0.75 Amps), setting the temperature at 40 C (104 F). I checked the temperatures daily for the next 10 weeks.

I took the remaining three cans to Winston Laboratories in Ridgefield, New Jersey. The lab tests revealed that a can of diet soda normally contains .06 percent aspartame.

In 1985, the National Soft Drink Association (NSDA) reported a similar experiment in which the aspartame in diet soda stored at 104 F (comparable to a daytime summer temperature in Phoenix, Arizona) turned into formaldehyde. The NSDA has recommended that aspartame not be approved for use in soda.

On April 1, I took the soda cans out of the refrigerator, out of my room and out of the incubator, and I brought the samples to Winston Laboratory for analysis.

I was going to do a taste test in my sister's fourth-grade class, but the school nurse said that I couldn't, because of all the bad things people say about aspartame; so instead I tested the samples on a group of adults.

The Taste (and Waste) Tests

I performed a double-blind experiment. My mother helped label each sample, including newly purchased Diet Coke samples, with a number.

There was an obvious preference for the just-bought Diet Coke. The scores for the incubator sample were very low. Nearly everybody hated the taste.

Since the aspartame in diet soda breaks down into formaldehyde and DKP, it makes sense that taste tests revealed a noticeable difference among tasters. The higher the storage heat, the worse the taste.

Winston Laboratories reported the following results. In the refrigerated sample, 0.058 percent aspartame remained: The missing portion turned into 0.001 percent DKP and 53.5 parts per billion formaldehyde. In the sample from my room, all that was left of the aspartame was 0.051 percent. The missing portion had turned into 0.002 percent DKP and 231 parts per billion formaldehyde. In the incubator sample, there was only 0.026 percent aspartame, but 0.010 percent DKP and 76.2 parts per billion formaldehyde.

The higher the storage temperature, the higher the level of DKP in the soda. Room temperature seems to create the highest levels of formaldehyde in soda. At very high temperatures, the formaldehyde breaks down. However, even when refrigerated, the aspartame breaks down into formaldehyde.

Concerning aspartame, the FDA says, "We believe, based on all the information that we received to date, that this is a safe product."

I say, "Decide for yourself."

The total cost of testing was $1,250. This may not be a lot of money to a drug company, but it is to me. As it is, I will be babysitting for the whole summer of 1997 to pay for the study.