How we know what we know

In 1971, Jack, my husband of three years, left hospital administration to become an investment banker, traveling the country, making presentations. And two abnormal things happened. First when landing at his destination, Jack appeared to be drunk: unsteady on his feet and unable to respond to questions. But he recovered by immediately going to a motel and sleeping for three hours before going to his meeting. In addition, Jack would lose consciousness in some, but not all restaurants.

I knew nothing about this. But after we flew to New Mexico on vacation and I watched Jack collapse while eating dinner, I pulled the story out of him. And the morning after returning to Chicago, Jack, at my insistence, was in his physician’s office.

Monte Levinson, M.D., subjected Jack to virtually every diagnostic procedure available. “Jack, we’ve done all these tests and you’re in perfect health. There is absolutely nothing wrong with you. However, there is one test that isn’t back yet. Call me tomorrow morning and I’ll give you that result. In the meantime I think you and Adrienne should just relax. There’s an absolutely incredible new restaurant you’ll enjoy. Promise that you’ll take your wife there for dinner tonight.”

The next morning Jack called Dr. Levinson. “Was that a great place?” was the first thing Levinson said.

“Well the food was wonderful,” Jack responded, “but as a matter of fact I got so very sick that Adrienne had to drive home.”

“I thought so. That was the last test. You’re MSG sensitive.


Five years before the Truth in Labeling Campaign was incorporated we understood little about Jack’s sensitivity.  We knew only that it was brought on by ingestion of monosodium glutamate and other food additives that contained the toxic component of monosodium glutamate, i.e., processed free glutamic acid (MfG). So, I began to ask questions. What, exactly, caused his reactions? Why did some people react, while others did not? But I found it extraordinarily difficult to look for answers when I didn’t know what the questions should be.

I started with the phone book looking up “dietician,” and “nutrition,” and “FDA.” I called colleges and universities, and when those to whom I spoke couldn’t answer my questions, I asked them to tell me who could. The first call that paid off was to the University of Illinois, where I was referred to Dr. Steve Taylor at the University of Nebraska — “the authority on MSG.” The Institute of Food Technologists, an association of people concerned with design and implementation of chemicals to be used in processed foods, also referred me to Dr. Steve Taylor. The American Dietetic Association, the American Medical Association, and the FDA referred me to The Glutamate Association.

I spoke to Richard Cristol at The Glutamate Association. He assured me that Jack could not possibly be sensitive to MSG, and he sent me a book that, he said, would prove it. Richard Cristol also suggested that I speak to Steve Taylor, who also assured me that Jack could not be sensitive to MSG, and suggested that I speak to Richard Cristol at The Glutamate Association.

I had come full circle.

Only later did I come to understand that The Glutamate Association (Richard Cristol, chairman) had been set up by Ajinomoto, U.S. producer of MSG, to promote sales of MSG, and that Steve Taylor, as professor at the University of Nebraska, wrote and spoke out on the safety of MSG without acknowledging that he was a paid agent of Ajinomoto.

The book sent by Richard Cristol, Glutamic Acid: Advances in Biochemistry and Physiology(1), contained the proceedings of a symposium held in May, 1978 in Milan, Italy, for the thinly veiled purpose of appearing to prove that MSG was safe. It was almost immediately obvious that the research reported was, for the most part, built on inappropriate methodology and/or drew conclusions that did not follow from the results of the studies. There were, however, a limited number of papers that appeared to contain more than propaganda. One by John Olney was particularly interesting, and I set out to read more.

I read everything I could find on the subject. When I couldn’t understand what an author was saying, I went to the children’s section of the library and took out elementary science books. I read dictionaries, encyclopedias, books, and journals. I had no difficulty reading scientific articles, and quickly discovered that there were two distinct sorts of studies: those that set out to uncover the truth, whatever that might be; and those that set out to lend credibility to the notion that monosodium glutamate was safe.

Some studies seemed to conclude that monosodium glutamate was a harmless substance, while other studies concluded that monosodium glutamate was toxic. That was very interesting to me as a researcher, but told me nothing about the nature of the ingredients that caused Jack’s debilitating reactions, and why some people, but not all, suffered similar reactions. And that, after all, was what I was desperate to know.

The answers did come eventually, not from studies of the safety/toxicity of monosodium glutamate, but from individual consumers, manufacturers, food chemists, food technologists, food encyclopedias, trade magazines, people Jack met on airplanes, and intuition.

First Jack and I came to understand that all of the adverse reaction triggers named by Dr. Schwartz in his book, In Bad Taste, the MSG Syndrome, contained free glutamic acid, i.e., glutamic acid that existed separate and distinct from protein. It was only as consumers began reporting that they reacted to products in addition to those with ingredients named by Dr. Schwartz, that we began to realize that MSG-reactions were always associated with ingredients that contained manufactured free glutamic acid, whether freed from protein through some manufacturing process or through fermentation, or produced by genetically modified bacteria that were grown to excrete monosodium glutamate through their cell walls.

From trade journal articles and advertisements I learned that ingredients that contained processed free glutamic acid could be substituted for monosodium glutamate without sacrificing the perception of desirable taste. In addition, I learned that people in the flavoring industry understood that there was profit to be made from monosodium glutamate substitutes that had “clean labels,” i.e., labels that gave no indication that there was anything related to MSG in the product.

From a study done by Rundlett and Armstrong(2), I learned that processed food that contained free L-glutamic acid invariably contained free D-glutamic acid — a concept that had never occurred to me. And with that knowledge, I was able to search out information about the various impurities found in monosodium glutamate and the other ingredients that contained MSG. I even found an explanation of impurities present in monosodium glutamate tucked away in the files of the FDA’s Dockets Management office.

On the Internet, I found copies of patents associated with the production of monosodium glutamate, and from that learned that beginning in 1957, Ajinomoto’s monosodium glutamate was made by a process of bacterial fermentation – a new process — wherein carefully selected genetically modified bacteria that were fed on various carbohydrate media secreted glutamic acid through their cell walls. It appeared that the “monosodium glutamate” made previously by extraction without the aid of genetically modified bacteria (prior to 1957), and much of the “monosodium glutamate” for sale in the United States after 1957, were not one and the same.

Before I was finished, I realized that any glutamic acid that was ingested as a single amino acid (with or without other single amino acids) would cause what we called MSG reactions in people who exceeded their tolerances for the substance. I also came to understand that the free glutamic acid (MfG) can be intentionally produced/manufactured in food or chemical plants by acid hydrolysis, autolysis, enzymolysis, or bacterial fermentation; and MfG will be produced, sometimes unintentionally, when a protein source is left to ferment.

I found that MfG can be produced through a complex cooking process wherein a product referred to as a “reaction flavor” is produced from a combination of specific amino acids, reducing sugars, animal or vegetable fats or oils, and optional ingredients including hydrolyzed vegetable protein.

And last but not least, I found that acid hydrolyzed proteins contain carcinogenic mono and dichloropropanols(3,4), and reactions flavors contain carcinogenic heterocyclic amines(5,6).

As pieces of the puzzle came together, I began to give serious consideration to the discrepancies in the published literature: the so-called scientific studies. I knew that MSG caused adverse reactions. How could it be, then, that industry was able to produce studies from which it could conclude that MSG was safe?

The key to understanding how data could be so manipulated — to come up with the convenient conclusion that monosodium glutamate was a harmless flavor enhancer — still eluded me. Through careful re-reading of each industry-sponsored study, I became aware that none met the assumptions of the statistical tests used and cited, and on that basis alone the conclusions drawn from each and every study were invalid. But there had to be something more.

And there was something more. In the double-blind studies, where subjects ingested monosodium glutamate on one occasion and a placebo on another, researchers reported that there were as many responses to placebos as there were to monosodium glutamate test material. Jack and I both knew that could not be true — unless, of course, those placebos were not truly inert, as placebos must be. But that was unthinkable. It was unthinkable that anyone — anyone — would lace placebos with material that might cause adverse reactions.

By the beginning of 1991, however, I was thinking the unthinkable, and was sharing my concerns with Jack. And on February 4, 1991, at the Federation of American Societies for Experimental Biology (FASEB) hearing on the Safety of Amino Acids Used in Dietary Supplements, Jack questioned the propriety of placebo material being used by the International Glutamate Technical Committee (IGTC) in their double-blind studies of the safety of monosodium glutamate. We only found out much later that in a March 22, 1991 letter written in response to a question raised by Sue Anne Anderson, R.D., Ph.D., Senior Staff Scientist with the Life Sciences Research Office at FASEB, IGTC chairman Ebert acknowledged that since 1978 all of the placebos in double blind IGTC-sponsored studies had been laced with aspartame — an ingredient that contains aspartic acid and causes brain lesions, endocrine disorders, migraine headache, depression and all the other reactions that can be caused by the free glutamic acid found in monosodium glutamate, hydrolyzed protein products, autolyzed yeast, etc.

I had started my quest with two questions, the first being, “What is the nature of the products that cause Jack’s reactions?” But before I found the answer to that first question, two others had been raised. First, given the fact that monosodium glutamate and the other ingredients that contain MfG have toxic potential, and there are no studies from which it could be legitimately concluded that monosodium glutamate is “safe,” why does the FDA allow the intentional addition of MSG and MfG to processed food? And second, why isn’t the US population aware of the toxic potential of MSG and MfG?

Adrienne Samuels


1. Glutamic acid: advance in biochemistry and physiology. Filer LJ Jr., Garattini S, Kare MR, Reynolds WA, Wurtman RJ (Eds), 
New York: Raven, 1979.

2. Rundlett KL, Armstrong DW. Evaluation of free D-glutamate in processed foods. Chirality. 1994;6:277-282.

3. Pommer K. New Proteolytic enzymes for the production of savory ingredients. Cereal Foods World.1995;40(10):745-748.

4. Food Chemical News, Dec 2, 1996. pp24-25.5.

5. Lin LJ. Regulatory status of maillard reactions flavors, Washington DC: Division of Food and Color Additives, Center for Food Safety and Applied Nutrition, Food and Drug Administration. Paper presented at a meeting of the American Chemical Society, August 24, 1992.

6. Food Chemical News, May 31, 1993. p16.