Dr. Blaylock's 1999 letter to Minneapolis Neuropathy Association

By Neurosurgeon Russell Blaylock, M.D.
(c) 1999
February 10, l999

Minneapolis Neuropathy Association
Mr. Al Porte
P. O. Box 14901
Minneapolis, Mn 55414

Dear Mr. Porte:

I was asked to write to you about my concerns regarding the sweetener aspartame, especially as regards neurological disorders. As you may know, complaints against aspartame constitute 75% of all additive related complaints relayed to the FDA department of consumer complaints. Until recently, these were merely written off as anecdotal observations of little scientific validity. But recent findings have shed some light on this elusive compound and its deleterious effects of the human population .

Aspartame an L aspartyl L phenylalanine methyl ester, is composed of two amino acids, aspartate and phenylalanine, linked by methanol. Inside the gastrointestinal tract, especially in the stomach it is bro ken down into its constitutent components . In some instances the dipeptide is lysed within the cells of the gut. As a consequence the methanol is rapidly absored and distributed throughout the tissues of the body. Within the tissues substantial amounts of methanol's two metabolic breakdown products (formaldehyde and formic acid) have been shown to accumulate in many tissues."

These breakdown products, formaldehyde and formic acid, have been shown in several important studies, to be extremely toxic to tissues in very small doses. In fact, even small doses of formaldehyde are considered to be carcinogenic. A recent study by Trocho, Pardo and co- workers, have demonstrated that following aspartame ingestion, significant amounts of formaldehyde accumulate in the tissues. Formaldehyde is known to bind strongly to proteins and nucleic acids , forming adducts that are extremely difficult to eliminate through normal metabolic pathways."

In this study, they demonstrated that labeled methanol (as formaldehyde) accumulated in high concentrations in the liver (50%) and in lower, but substantial, concentrations in the kidney, adipose tissue, brain and retina. Within the cell, they found large amounts located within the DNA. It was interesting to note ethat these doses were lower than that used in toxicity studies. Previous studies have shown that very high doses of aspartame may not cause acute symptomatology. This study indicates that the damage may necessitate longer periods of time to manifest itself, and that the eventual effects can be quite deleterius.

The doses used were within those recommended by the FDA as ADI for humans. This is especially of conern in children who may consume doses of aspartame as high as 75 to 90mg/kg. It is also important to note that in this study, the formaldehyde was accumulative as were its injury to cellular proteins and DNA. In the real life situation, humans are exposed to repeated doses of aspartame found in many foods, drinks, medicines and chewing gum.

An earlier study by Shephard and co -workers, it was found that aspartame is nitrosated within the gut and that this nitrosation of the amine group is "quite cytotoxic" and represents a moderately strong mutagen in the Ames test.

Another recent study, by Sorg, Willis and co-workers is also alarming. In this study, it was found that prolonged exposure to low concenetrations of formaldehyde could cause chemical sensitization to cocaine, via a limbic mechanism. With increasing reports of multiple chemical sensitivity syndrome, one must be concerned about chronic low dose formaldehyde exposure via aspartame."

In addition, a l997 study found that macrophages exposed to aspartame produces a threefold rise in leukotriene (B4, C 4 and 15 hydroxyeicosatetraenoic acid) and arachidonic acid metabolites. This would be detrimental to patients having autoimmune disorders such as lupus, multiple sclerosis and rheumatoid arthritis. Clinically, there is some evidence for worsening of two of the three conditions (MS and Lupus) by aspartame use.

Finally, in the diabetic, great concern must be expressed about the danger of toxin damage to already weakened peripheral nerves in the diabetic situation. With the buildup of accumulated concentrations of formaldehyde and formic acid in nervous tissue, long term damage and drapid progression of diabetic peripheral neuropathy is almost a given. We know that all of the components of aspartame are neurotoxic as well as most of its breakdown products, such as diketopiperazine, phenylethalamine, phenylalanine, aspartic acid, and methanol (formaldehyde and formic acid) Aspartic acid is a known excitotoxin and in the body is converted to glutamic acid, an even more poewrful excitotoxin. Experimentally, the same widespread brain lesions produced by MSG exposure can be produced by high dose aspartame exposure.

It is my opinion, and the opinion of many others, that aspartame is a dangerous neurotoxin and its use should be discouraged generally, but especially so in those harboring neurological diseases.

Sincerely yours,
Russell L. Blaylock, M.D.


1. Shephard SE, Wakabayashi K and Nagao M. Mutagenic activity of peptides and the artificial sweetener aspartame after nitrosation. Food Chem Tox 31Z : 323-329, 1993.

2. Sorg BA, Willis JR , et al. Repeated low-dose formaldehyde exposure produces cross-sensitization to cocaine; possible relevance to chemical sensitivity in humans. Neuropsychopharmacol 18 :385, 394, l998

3. Trocho C, Pardo R, et al, Formaldehyde derived from dietary aspartame binds to tissue components in vivo. Life Sciences 63:337- 349,199

4. Hardcastle JE, B ruch RT. Effect of L-aspartyl-L -phenylalanine methyl ester on leukotriene biosynthesis in macrophage cells. Prostagland Leukot Essen Fatty Acids 57: 331-333,1997.


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Excitotoxins: The Taste That Kills (Paperback) by Russell L. Blaylock

It is almost a cliche in this day and age for someone to ask the waiter at a Chinese restaurant 'no MSG, please,' as is the waiter's knowing smirk in response. MonoSodium Glutamate (MSG), or 'The essence of taste' (as coined by the Japanese), is used as a 'taste-enhancer' in nearly every form of processed food on the market today, though 'taste addiction' may be a more correct term. But what exactly does it do? And how is it harmful?

Dr. Russell L. Blaylock answers these questions and poses some startling evidence as to the eventual consequences of a heavy MSG-diet in his book _Excitotoxins: The Taste that Kills_. In basic terms, MSG (and other, similar agents) pierces the blood-brain barrier and over-stimulates the neurons of a brain to a deadly degree. Habitual intake among animal experiments has shown the development of tumors, memory loss, and a whole host of neurodegenerative diseases as the end result of excess excitotoxin intake, including Alzhiemer's, Parkenson's, Lou Gerhig's etc.

Walk into any gas station in the United States (or grocery store, for that matter) and, upon close investigation, you will find that 75%-90% of the available food has been 'enhanced' to some degree by excitotoxins. The chemical agents are often disguised by such ambiguous terms as 'spice' and 'natural flavors' or, my personal favorite, 'hydrolyzed vegetable protein.' A consumer society must have consumer slaves to keep it functioning; MSG is the crack cocaine of the food industry...and it is legally perpetuated by slush-fund advocates and a pork-glutted FDA. As proven again and again, money talks, ... [you can finish the maxim for me].

Blaylock's thesis is written in a technical style, but the use of repetition throughout each chapter hammer in his myriad points into the reader with precision and power. An important book for anyone concerned with the health of self and family. You are what you eat---but do you know _what_ it is you are eating, below the surface of taste/fulfillment?

If you or someone you know
drinks diet soda check out the
Aspartame Victims Support Group at