The Truth About Aspartame Toxicity & Nancy Markle

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Aspartame (NutraSweet) Toxicity Information Center

A "World Environmental Conference" email has been working its way around the Internet. The World Environmental Conference did occur with an EPA representative speaking and the discussion turning to aspartame toxicity. However, the summary was not written by Nancy Markle. Because there are a few scientific inaccuracies in the email, Monsanto/NutraSweet may attempt to create the image that aspartame poisoning is a hoax and that the email is a hoax. As independent researchers know, this is definately not the case.

A short summary of the aspartame toxicity issue will be presented below. Please see the case histories, scientific FAQs, and other important details on the Aspartame / NutraSweet Toxicity Information Center web page for more details. In addition, please see the Healthier Sweetener Resource Center web page for details on finding healthier sweeteners for the general population, dieters, and diabetics, so as to avoid switching from one toxic sweetener to another.

Aspartame is a dipeptide, but breaks down into the following chemicals: methanol (wood alchol) -- whether aspartame is heated or not, aspartic acid, phenylalanine, aspartylphenylalanine diketopiperazine (DKP), beta-aspartame, and a few odds and ends.

The methanol is absorbed and converted to formaldehyde in the body. Formaldehyde is known to cause damage to the immune system, nervous system, and irreversible genetic damage at very low-level, long-term exposure. The most recent evidence (this year) indicates that the formaldehyde from aspartame ingestion accumulates in the body as "adducts":

A few comments from independent research scientists regarding this and other recent aspartame research:

The independent scientists and physicians who claim that aspartame causes toxicity, base their claims on three areas:

  1. Significant toxicity of aspartame metabolites (e.g., formaldehyde) seen in numerous scientific studies.

  2. Nearly 100% of the independent research has found problems with aspartame. This includes animal studies and controlled human studies (as well as double-blind studies).

  3. An enormous number of people have reported serious toxicity reactions from extended use of aspartame including seizures, vision loss, neuropathy symptoms, loss of blood sugar control, nausea, memory loss, depression, and other signs of gradual damage to the body's neurological and immunological systems.

    More details on a. - c. follows:

    1. Toxic metabolites. Aspartame breaks down into methanol (wood alcohol) -- whether it is heated or not, free-form aspartic acid, aspartylphenylalanine diketopiperazine (DKP), phenylalanine, beta-aspartame, and a few other chemicals. The methanol, free-form aspartic acid and DKP appear to represent the most significant hazards:

      • Methanol -- is absorbed and converted to formaldehyde. Formaldehyde has been shown to cause gradual damage to the immune system, nervous system, and irreversible genetic damage. The manufacturer, played a number of games to convince scientists that the methanol-->formaldehyde was not a problem. Addressing a few:

        1. "Methanol is found in alcoholic beverages and fruits at 10 times higher levels than in aspartame"

          A. Both alcoholic beverages and fruits have been shown to contain protective factors which prevent methanol conversion to formaldehyde and subsequent toxicity.

        2. "Methanol levels are too low to cause toxicity"

          A. They are only too low to cause immediate death. They are within the range necessary to cause chronic, low-level poisoning. The same can be said of the formaldehyde.

        3. "Methanol levels do not rise after aspartame ingestion."

          A. The aspartame manufacturers funded 13 years of studies where a 1960's methanol testing procedure was used. The method used was incapable of registering any increase from normal aspartame ingestion. A properly-conducted test in the mid-1980's showed a significant increase from the equivalent of one can of soda in a 30 kg child.

          4) "The body contains methanol and formaldehyde already"

          A. Metabolism does create an extremely low level of methanol and formaldehyde in the body. However, these levels are very tightly controlled. Even as little as 0.75 mg of formaldehyde exposure in children (daily for several months) has been shown to cause chronic toxicity.

          5) "Formaldehyde is found in some foods"

          A. Formaldehyde is extremely toxic once it makes it into the bloodstream and the rest of the body. The digestive system can break down formaldehyde before it reaches the bloodstream. With aspartame, however, it is absorbed as methanol and breaks down into formaldehyde after it is already in the bloodstream. (Actualy, methanol is break down into formic acid in other areas such as the eye, for example.)

          6) "People ingesting aspartame do not have increases in formic acid levels"

          A. Formaldehyde breaks down into formic acid (aka formate) in the body. However, it appears that with aspartame, the formaldehyde accumulates in the body as "adducts." Even if it didn't though, having excess levels of formaldehyde passing through the body is a significant toxicity hazard. The manufacturers used urine formic acid measurements. It has recently been shown that such measurements are not reliable for low-level, chronic formaldehyde poisoning. The technique they used for plasma formic acid measurements was flawed and has been called "notoriously inaccurate" by one formic acid researcher.

      • Aspartic acid.

        It is well-known that excitotoxic amino acids such as aspartic acid can be used in conjunction with formaldehyde to increase pain and adverse effects on the nervous system. The aspartic acid is in "free-form" (unbound to protein), so unike food, it is absorbed suddently, bypassing the normal absorption and metabolism process. Combining this with formaldehyde from aspartame is bound to increase the gradual damage.

      • Aspartylphenylalanine diketopiperazine (DKP)

        The DKP is suspected to be converted in the gut into a potential brain tumor agent. One of the most reknowned neuroscientists in the world called this an "enormously complex subject" so this piece won't go into too many details.

        There were two pre-approval studies which showed (upon *independent* review) to cause dose-related brain tumors in the test animals. DKP appears to be able to cause mutations (although I think the formaldehyde could be a candidate as well). A recent review of the epidemiological data shows a rise in certain types of brain tumors (the same in the animals) in the most susceptible population group within several years after aspartame came on the market.

        1. "A recent study (Gurney) did not show a rise in brain tumors"

          A. That study looked at children. Children would be considered to be the least likely population group to experience the aspartame-caused brain tumor. The study by Olney focused on the middle aged and older population group.

        2. "Brain tumors rates have been increasing since before aspartame was approved."

          A. A brain tumor in adults can take many years or decades to become large and easily detectable. Aspartame couldn't have been the original cause of these brain tumors because it wasn't on the market long enough. However, it is known that certain less deadly brain tumors can transform into more deadly and larger forms in a shorter period of time. If aspartame was a brain tumor agent, that is what we would see first. Olney showed that in the most susceptible population group, there has been an enormous increase in these deadly types of brain tumors since within a few years after aspartame appeared on the market. Of course, there has been a corresponding decrease in the less deadly types of brain tumors during that time. That is why the *overall* brain tumor rate looks somewhat stable. So, whenever some government official talks about *overall* brain tumor rates, they clearly didn't read the Olney study.

        3. "Ishii study in Japan showed that aspartame didn't cause brain tumors"

          A. The study was conducted by a close business partner of the manufacturer. At the time, this company who was leading the International Technical Glutamate Committee and sponsoring research with aspartame hidden in the beverages given to the control group during double-blind MSG "research." There is a long history of what I think is clearly scientific fraud on the part of this group who sponsored the research. Still, even if the study is accepted, there are two pre-approval studies with opposite results.

        4. "The animals were given high doses of aspartame"

          A. The metabolites of aspartame are anywhere from 5 to 60 times more toxic in humans than in rodents (dependent upon the metabolite). So high doses are required to simulate human ingestion.

    2. Independent studies find problems

      Please see: Survey of the Scientific Literature by Researcher

      The reason the manufacturers studies never find problems (at least never report them in the abstract) is that they play games (not unlike the tobacco industry). For example, nearly 100% of the subjects in their aspartame and seizure studies were on anti-seizure medication. Another study found that aspartame caused more problems than placebo, so they split up the reactions into enough tiny categories so they could claim in the abstract that there was no significant difference within the categories (e.g., 1 reaction to aspartame in a tiny category is not a significant difference (statistically) than 0 reactions to placebo in that category). (Note: this severely flawed study is often passed around on the Net. It is: "Safety of Long-Term Large Doses of Aspartame," Archives of Internal Medicine, Volume 149, page 2318-2324)

      Number of and types toxicity reactions.

      Please see the following for an analysis:

      Reported Aspartame Reactions

      and the following page for samples of cases:

      Samples of Reported Toxicity Reactions