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Controversy over exitotoxins

  1. Jun 28, 2005 #1
    I just found out about the controversy over exitotoxins that arose from the research of Dr. Russel Blaylock. I guess this news is a couple years old now, and I've skimmed a few web sites but didn't find anything really recent. Here's one:

    Fake Sweetener Largely Behind Cognitive Disfunctions | 100777.com

    Is anyone up to date about this? Has this research been further confirmed, or refuted?
  2. jcsd
  3. Jun 28, 2005 #2


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    I'll have to dig into this a little further to qualify the work, but I'm a little suspicious at first glance mainly because it's spelled "excitotoxin", from the ability to "excite" certain nervous system responses. Perhaps using this as the more common search term will aid your search effort, Zoob?
  4. Jun 28, 2005 #3

    Math Is Hard

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    A class action suit's a brewin'... https://www.lawyersandsettlements.com/case/aspartame?ref=aspartame_overture

  5. Jun 28, 2005 #4
  6. Jun 28, 2005 #5
    I don't really want to scour the web, because the several sites I already found all keep pointing back to Dr. Russel Blaylock. That made me curious to know if he was a lone alarmist.

    I posted in case you, Moonbear, Monique, or anyone had seen anything recent in Biology journals or any non-web sources seconding his opinion.

    Yes, these substances are toxically exiting. Apparently they kill neurons by getting them so exited they die of exhaustion. MSG and Aspartame.
  7. Jun 28, 2005 #6


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    It's a hoax...an urban legend.

    I was wondering why all the websites that mentioned this were not medical or scientific sites (always an indicator something's fishy). Not to mention the claims on some of these sites were ludicrous. NutraSweet=Hitler. That was a good one. :rofl:

    Here is the truth.

    FDA Statement on Aspartame (FDA):

    Analysis of the National Cancer Institute's public data base on cancer incidence in the United States — the SEER Program — does not support an association between the use of aspartame and increased incidence of brain tumors.

    Study Reaffirms Safety of Aspartame (MIT News):

    Even daily large doses of the high-intensity sweetener aspartame, also known as NutraSweet, had no adverse effect on study subjects' health and well-being, a visiting scientist at MIT reported in the American Journal of Clinical Nutrition last week.

    "We conclude that aspartame is safe for the general population," said Paul A. Spiers, visiting scientist in the Clinical Research Center (CRC).

    A Web of Deceit (TIME magazine):

    A widely disseminated e-mail by a "Nancy Markle" links aspartame to Alzheimer's, birth defects, brain cancer, diabetes, Gulf War syndrome, lupus, multiple sclerosis and seizures. Right away, the long list warrants skepticism. Just as no single chemical cures everything, none causes everything.

  8. Jun 28, 2005 #7
    while the extent of toxicity may be exagerated, biochemically i could see how when aspartame is cleaved by trypsin in the stomach, it will release methanol.
  9. Jun 28, 2005 #8


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    Yes, it does and a glass of tomato juice produces 4 times as much methanol as a can of Diet Coke. It's in the Time article linked to on the Snopes site.

    "Aspartame leads to "methanol toxicity." Not even close. Trace
    amounts of methanol exist naturally in many fruits and vegetables, and
    a tiny amount is released whenever the body digests aspartame. But
    there's four times as much methanol in a glass of tomato juice as in a
    can of aspartame-sweetened soda, and our bodies have no trouble
    handling such a tiny amount."
  10. Jun 28, 2005 #9
    Well, the book in question seems actually to exist:

    Amazon.com: Books: Excitotoxins: The Taste That Kills

    So, I doubt it's an outright hoax. (I know what you mean about the sitenames, but I found some when I googled "exitotoxins" that were not exaggerated sounding.)

    However, the guy may be all on his own, out in left field, fighting the FDA approval.
  11. Jun 28, 2005 #10


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    Yeah, I had seen that on Amazon's site, got to love how the author keeps claiming he's not a crackpot in the reviews. :wink:

    Maybe he really believes in what he's saying, there doesn't seem to be anyone with credentials backing him up though.
  12. Jun 28, 2005 #11
    This is what I was wondering, since I couldn't find this notion leading anywhere except back to him.
  13. Jun 29, 2005 #12


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    I did a PubMed search using the keywords: aspartame toxicity
    It came up with only 5 pages of references, which is a fairly small number of articles for anything that general. As I skimmed through, most of them are letters, not actual research articles, others are testing aspartame for interactions in other models of toxicity (I didn't read them, just from skimming it was clear it wasn't what you're looking for). The only relevant paper I came across is a review written by the folks working for NutraSweet that concludes it's safe (yes, there is a clear potential for conflict of interest there). I didn't come across anything that refutes that claim though, other than that if you administer it intraperitoneally to rats instead of orally, their wheel-running is decreased, but that really doesn't mean much unless you're planning to inject yourself with the stuff.

    Holder MD, Yirmiya R. Behavioral assessment of the toxicity of aspartame. 1989 Pharmacol Biochem Behav. 32:17-26.

    If there was any merit to those claims, I'd have expected to find at least a few legitimate articles claiming toxic effects.

    Just to add:
    Since in that book review, Blaylock was claiming to be a neurosurgeon with journal publications, I thought I'd check out his claims. These are the hits for his name on PubMed (I can only assume it's the same person since none of these are recent enough to get the full articles to check his full name).
    Considering the concentration of dates and how many have the same senior authors, and that these are all case reports, not actual experimental studies, I'd have to guess they were all written during a residency. Note that NONE of them are related to excitotoxins or in any way indicate that he has any degree of expertise in that area.

    Last edited: Jun 29, 2005
  14. Jun 29, 2005 #13
    Wow! Thanks Moonbear. Great research!

    I guess there's no plethora of support.
  15. Jun 29, 2005 #14


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    This is one of those interesting examples of how one man's theory can become another man's crusade. It is logical to question if something like aspartame or MSG could have potential toxic effects and I imagine the required hurdles were passed for that product to reach the market. But we all know that doesn't always ensure safety (Vioxx). So independent researchers conduct experiments to determine if certain chemicals convey any risk to the population. There can be considerable debate as to the conclusions reached in certain studies and even for those chemicals that are proven to cause significant toxic effects in lab animals the debate still rages as to whether humans are truly affected. It usually comes down to a weight of evidence comparison and the precautionary principle to then assume that this compound is toxic and this one is not. In the specific case we are examining, the majority of the evidence suggests that human use of these compounds entails little risk, but some people just can't give up the attention they may be receiving by disseminating this type of "information".
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