Glutamic acid: initiator of the obesity epidemic

Adrienne Samuels, Ph.D., March, 2022 

NOTE: Studies confirming that the free glutamate in MSG causes brain damage, intractable obesity, infertility and more were done before it was understood that excitotoxic free glutamate would be found in ingredients other than MSG.


Obesity is the excessive or abnormal accumulation of fat or adipose tissue in the body that impairs health through its association with numerous serious diseases and health conditions.  It is a public health epidemic with an economic burden estimated to be about $100 billion annually in the United States alone (1).  

According to the Centers for Disease Control and Prevention (CDC), those who are obese, compared to those with a healthy weight, are at increased risk for many serious diseases and health conditions, including the following:    

  • All-causes of death (mortality)
  • High blood pressure (hypertension)
  • High LDL cholesterol, low HDL cholesterol, or high levels of triglycerides (Dyslipidemia)
  • Type 2 diabetes
  • Coronary heart disease
  • Stroke
  • Gallbladder disease
  • Osteoarthritis (a breakdown of cartilage and bone within a joint)
  • Sleep apnea and breathing problems
  • Many types of cancers
  • Low quality of life
  • Mental illness such as clinical depression, anxiety, and other mental disorders
  • Body pain and difficulty with physical functioning (2).

There are countless factors that contribute to obesity, but only one that by itself can explain the ongoing obesity epidemic:the fact that excitotoxic amino acids (EAA) ingested by pregnant women are passed via the placenta to their fetuses where they cause brain lesions in the arcuate nucleus – brain damage that is followed by gross obesity as these children approach maturity.

A series of studies from 1969 and the decade that followed demonstrated that three conditions had to be met in order to produce food-induced neurotoxicity:  

  • A vulnerable brain (immature or damaged). 
  • A sufficient quantity of excitotoxic material to cause that material to become excitotoxic.   
  • A way for that excess material to be delivered to the vulnerable brain.

Damage caused by manufactured free glutamate delivered by pregnant women to the vulnerable brains of their fetuses meets all three of these conditions.  A sufficient quantity of excitotoxic material became available and accessible in 1957 when vast amounts of free glutamate began to appear in processed food.


Undisputed is the fact that there are high concentrations of glutamate in the brain.  When present in protein or released from protein in a regulated fashion (through routine digestion) glutamate is vital for normal body function. Glutamate is the principal neurotransmitter in humans, carrying nerve impulses from glutamate stimuli to glutamate receptors throughout the body.

Disputed by some producers of free glutamate is the assertion that glutamate is an excitotoxic amino acid.  This Jekyll and Hyde amino acid becomes toxic when present in greater quantity than a healthy human needs for normal body function. Then, as an excitotoxic neurotransmitter, it fires repeatedly, damaging targeted glutamate receptors and/or causing neuronal and non-neuronal death by over exciting those glutamate receptors until their host cells die (3-8).

Glutamate-induced brain damage

The first study to address the possibility that glutamate from exogenous sources (from eating, for example) might cause brain damage was published in 1969. At the time, it was demonstrated that glutamate-induced brain damage to the arcuate nucleus of the hypothalamus of neonatal animals was followed by obesity, reproductive dysfunction, behavioral disturbances and more (9).  In the decade that followed, research confirmed that glutamate given as monosodium glutamate administered or fed to neonatal animals causes hypothalamic damage, endocrine disruption, and behavior disorders after either subcutaneous (10-31) or oral (17,23,24,26,32-36) doses. 

Developmental dysfunction or abnormalities in growth and behavior were also noted in a number of studies. Animals treated with glutamate as neonates or in the first 12 days of life suffer neuroendocrine disturbances including obesity and stunting, abnormalities of the reproductive system, and underdevelopment of certain endocrine glands (9,18,20,36,37-54) and possible learning deficits either immediately or in later life (40,43,44,55-61).

In addition, Bhagavan and others reported behavioral reactions including somnolence and seizures (62-69; tail automutilation; (42,56) and learned taste aversion (58). Irritability to touch was interpreted as conspicuous emotional change by Nemeroff (42). Lynch (70) reported hyperglycemia along with growth suppression. He noted that hyperglycemia did not occur when subjects were given intact protein that contained a large amount of glutamate.

Since the 1980s, researchers have focused on identifying and understanding human abnormalities associated with free glutamate, often for the purpose of finding drugs that would mitigate glutamate’s adverse effects.  Invariably, those have been studies of the glutamate from endogenous sources.  The possibility that glutamate from exogenous sources might contribute to those abnormalities and/or might cause brain damage in humans leading to gross obesity, was not considered.

The case for the safety of MSG

Brain lesions

In the 1960s and 1970s, research done by people not employed by the glutamate industry demonstrated that monosodium glutamate fed to laboratory animals causes brain lesions, endocrine disorders, and observable adverse reactions.

In response, glutamate-industry researchers pretended to replicate those animal studies; but changed the methodology enough to make certain that there would be nothing negative to report.  

 These investigators made no attempt to replicate the methods of the independent scientists, and used entirely different (and inappropriate) methods for preservation and staining brain tissue in the analysis of results. 

On occasion, I had the privilege of visiting with John W. Olney, MD, the man who coined the term “excitotoxin” to describe the effects he had seen free glutamate have on neonatal animals.  And while he didn’t dwell on criticizing the research of others, he was generous in answering my questions.  He told me that when he first found that glutamate (given as MSG) caused brain damage in infant mice, he searched out or was put in touch with Dr. W. Ann Reynolds, and either Reynolds or someone sent by Reynolds spent a great deal of time in Olney’s laboratory, learning the detail of how his experiments had been conducted.  By and large, it was Reynolds and coworkers Filer, Stegink, and Lemkey Johnson who failed to replicate Olney’s findings.  Other industry scientists producing similar results using similar methodology were affiliated with laboratories that did contract work for the glutamate industry.

Adverse reactions

Glutamate-induced adverse reactions may or may not involve the brain.  There has been no study of that issue. But since the subject of this paper is glutamate-induced obesity second to brain damage caused by glutamate ingested in quantity by pregnant women and passed to fetuses through the placenta, the subject of glutamate-induced adverse reactions has not been considered.

Establishment of excess free glutamate

It is necessary for a substantial amount of free glutamate to be ingested for that free glutamate to become excitotoxic.  For glutamate to be excitotoxic, there must be an accumulation of free glutamate greater than needed for normal body function.  

In 1957, bacterial fermentation was introduced as a new and improved method for production of free glutamate for use in food. From that point forward, with genetically modified bacteria secreting free glutamic acid through their cell walls, unlimited production of free glutamic acid was virtually assured (71).

It wasn’t long before competing manufacturers added dozens more excitotoxic food additives to the American diet. Following MSG’s surge in production and its manufacturer’s aggressive advertising, there was broad recognition that profits could be increased if a company produced its own flavor-enhancing additives. Since that time, the market has been flooded with flavor enhancers and protein substitutes that contain manufactured free glutamate such as hydrolyzed pea protein, yeast extracts, maltodextrin and soy protein isolate, as well as MSG. 

Although there have been studies that mention the fact that there are substantial amounts of free glutamic acid in processed food (72-80) there has been no systematic study. There are, however, numerous market reports with promotional materials that speak of manufactured glutamate history and forecast.  Market reports for monosodium glutamate focus on that commodity.  Market reports for glutamic acid generally take into account all flavor enhancers (81-87). 

You only have to compare the ingredients listed on the labels of processed and ultra-processed foods to a list of the hidden sources of manufactured free glutamate to realize just how much manufactured free glutamate there is in the food supply. Table 1 lists the food ingredients that contain free glutamate as an ingredient or a constituent of an ingredient. By virtue of the fact that ultra-processed foods are typically made with inferior foods and/or chemicals, every ultra-processed food contains flavor-enhancers, which will contain manufactured free glutamate regardless of the ingredient names on the labels describing those ingredients.   

Today, there is sufficient excitotoxic free glutamate in processed foods, dietary supplements, snacks, protein powders and protein drinks, protein substitutes, fake meat, enteral care products, and pharmaceuticals for a person to consume in a day’s time the quantity necessary for that free glutamate to become excitotoxic.  Only a portion of that comes in an ingredient called monosodium glutamate or E621. 

Since the 1957 change in method of MSG and manufactured free glutamate production, there are so many products that contain excitotoxic ingredients that it is easy for a consumer to ingest an excess of excitotoxic material during the course of a day.   

Effective delivery of excitotoxic free glutamateA way for that excess of glutamate to be delivered to the vulnerable brain.

Effective delivery of excitotoxic free glutamate would depend in large part on the integrity/health of the brain to which it is being delivered.

In children and adults with mature brains, delivery can be accomplished by providing the subject with free glutamate to ingest in sufficient quantity to cause it to be excitotoxic.

Delivery of excitotoxic free glutamate to a fetus and/or neonate will be accomplished when a pregnant or lactating female passes excess free glutamate to a fetus or neonate through the placenta or in mothers’ milk.

Nourishment (and not so nourishing material) is delivered to the fetus in the form of material ingested by a pregnant woman and passed to the fetus through the placenta. MSG can cross the placenta during pregnancy (88-90), can cross the blood brain barrier (BBB) in an unregulated manner during development (91-94), and can pass through the five circumventricular organs which are leaky at best at any stage of life (92,95).  Glutamate is an ingredient that passes to the fetus. The placenta does not filter out glutamate (88).   Moreover, the BBB is easily damaged by fever, stroke, trauma to the head, seizures, ingestion of MSG, and the normal process of aging (66,96). 

And the fetus will be more vulnerable to glutamate-insult than the newborn.

Similar to drugs and alcohol, free glutamate can also be passed to infants through mothers’ milk. Newborn humans will receive glutamate through mothers’ milk or through infant formula, both of which routinely contain free glutamate (97).

The glutamate in mothers’ milk, however, will not be excitotoxic unless lactating mothers ingest excessive quantities of free glutamate – quantities sufficient to cause free glutamate to become excitotoxic.

Onset of the obesity epidemic 

According to the Surgeon General’s “Vision for a Healthy and Fit Nation,” the prevalence of obesity changed relatively little during the 1960s and 1970s, but increased sharply over the ensuing decades (98).

That information is consistent with information that comes from the National Health and Nutrition Examination Surveys (NHANES) which periodically collect measured height and weights in representative samples of the population.  The first records of weight came from the CDC’s 1960-1962 report with subsequent reports confirming that the prevalence of obesity among adults more than doubled between 1976-1980 and 2007-2008 (99).

Summary and conclusions 

We have briefly discussed excitotoxicity, the phenomenon underlying the obesity epidemic, drawing attention to the fact that a possible role for excitotoxins from exogenous sources has not previously been considered. 

We have reviewed the studies that present evidence of glutamate excitotoxicity. Underscoring the recognition that glutamate-induced brain damage leads to obesity, is the fact that since 1980, it has been common practice to use monosodium glutamate or glutamic acid to produce brain-damaged obese animals for use in studies of various glutamate-related abnormalities.

We have described the way in which excitotoxic free glutamate can be delivered by pregnant women to fetuses and neonates, causing brain damage and subsequent obesity.

The single challenge to the assertion that the brains of the fetus and neonate are vulnerable to the toxic effects of glutamic acid from exogenous sources has been mounted by the International Glutamate Committee (IGTC) based on a paper Richard Hawkins presented in September 2008 at the IGTC’s 100th Anniversary Symposium of Umami Discovery: “The Roles of Glutamate in Taste, Gastrointestinal Function.”  

In 1969, the IGTC was organized to represent the interests of Ajinomoto, the U.S. producer of MSG and manufactured free glutamate. Hawkins received both travel expenses and an honorarium from the IGTC, and acknowledged the sharing of ideas and advice from Andrew Ebert, Ajinomoto’s agent in charge of providing test and placebo materials to their researchers doing double-blind studies on the safety of MSG.  It was Ebert who provided his researchers with placebos containing aspartic acid, an excitotoxic amino acid known to cause adverse reactions and brain damage identical to that caused by the excitotoxic glutamic acid in MSG test material. 

Without taking into consideration the unique properties of an immature brain, Hawkins asserted that the human brain is impervious to glutamate damage.

It has been demonstrated that following the 1957 modernization of glutamate production, there has been sufficient free glutamate available and accessible in processed and ultra-processed foods to cause accumulated glutamate to become excitotoxic.

From National Health and Nutrition Examination Surveys (NHANES) documenting the prevalence of overweight, obesity, and extreme obesity, we have observed increased incidence of obesity dating from 1960, as well as the demonstration of racial disparities. In the 2012 article “The Nation’s childhood obesity epidemic: Health disparities in the making,” Suzanne Johnson makes a case for the obesity epidemic being, in part, a product of an environment that promotes overeating — over time having changed the type and quantity of food we eat.  She cites less time for in home food preparation, the consumption of a plethora of fast food and convenience food, and the fact that fast-food restaurants are more common in ethnic minority neighborhoods (100).

The reader has only to connect the dots between 1) the vulnerable brain of the fetus and neonate receiving excitotoxic amino acids in processed and ultra-processed food, and 2) the fact that prior to the surge in production of glutamic acid triggered by the modernization of manufacture of the glutamic acid in MSG, there was no obesity epidemic.  Then trace the unfolding of the obesity epidemic from reformulation of free glutamate in 1957 to the early 1970s when those made obese by the influx of free glutamate began to become noticeable.  

Thus, it has been demonstrated that obesity can be caused by excitotoxic amino acids ingested by pregnant and/or nursing women and delivered to fetuses and neonates who exhibit obesity as they reach maturity.

No discussion would be complete without considering why this information has not been discussed previously by others.  With the first suggestion that MSG might have toxic potential, those with financial interest in promoting MSG as a valuable flavor-enhancer launched well-funded, well-articulated campaigns to promote their product and deny its toxicity. That included rigging studies to come to the foredrawn conclusion that MSG is a harmless food additive and securing the active cooperation of regulators as well as the help of medical professionals (101).

That might account for the fact that to date, the roles of MSG and manufactured free glutamate in the obesity epidemic have been overlooked.

Recognition of the fact that glutamate-induced brain damage in fetuses and neonates lies at the root of the obesity epidemic should serve as a valid starting point for new ground-breaking research. It should put an end to the shame and blame that have long been associated with obesity, and facilitate appropriate counseling and medical interventions for those who are afflicted. 

Excitotoxic amino acids delivered to fetuses and neonates by pregnant and nursing women should be included as recognized risk factors for obesity.  

References can be found here.

Types of products that contain processed free glutamic acid (FG)

In general…

Free glutamic acid, a.k.a. free glutamate (FG), the brain-damaging component of MSG can be used (and hidden) in processed foods, dietary supplements, cosmetics, personal care products, pharmaceuticals, and the food that is given to pets and other animals. It can be used in waxes applied to fresh fruits and vegetables. It can be used in ingredients used in pesticides, fungicides, fertilizers, and plant growth enhancers — remaining in the edible portion of the plant or on the edible portion of the plant when its leaves, fruits, nuts, grains, seeds, and other edible parts are brought to market.

There are over 60 food ingredients besides “monosodium glutamate” that contain processed free glutamic acid (FG). Each, according to the FDA, must be called by its own, unique, “common or usual name.” “Autolyzed yeast,” “maltodextrin,” “hydrolyzed pea protein,” and “sodium caseinate” are the common or usual names of some ingredients that contain FG. Unlike the ingredient called “monosodium glutamate,” they give the consumer no clue to the fact that there is FG in the ingredient.

In addition to ingredients that contain FG, some acids and enzymes when combined with a food that contains protein will produce FG. The words “enzyme” and “protease” (which is a type of enzyme) signal the presence of enzymes capable of causing the production of FG.

In particular…

– Low fat and no fat milk products often contain milk solids that contain FG. Other dairy products often contain guar gum and/or locust bean gum. Low fat and no fat versions of ice-cream and cheese may not be as obvious as yogurt, milk, cream, cream cheese, cottage cheese, etc., but they are not exceptions.

– Protein powders and protein drinks contain FG, and the FG in the protein powders and drinks will always be processed (manufactured), i.e., will always contain processed FG. Individual amino acids are not always listed on labels of protein powders and drinks.

– When this was written, there was an FDA requirement to give the name of the protein source when listing hydrolyzed protein products on labels of processed foods. Examples are hydrolyzed soy protein, hydrolyzed wheat protein, hydrolyzed pea protein, hydrolyzed whey protein, hydrolyzed, corn protein. If a tomato, for example, were whole, it would be identified as a tomato. Naming an ingredient “tomato protein” indicates that the tomato has been hydrolyzed, at least in part, and that processed FG is present.

– At one time, and maybe still, the FDA required disclosure of ingredients labeled “monosodium glutamate” and “hydrolyzed…protein” when, as ingredients, they are used in “flavor” or “flavoring” (whether or not the “flavor” or “flavoring” is preceded by the words “natural” or “artificial”). However, “flavors” and “flavorings” can contain FG in ingredients other than “monosodium glutamate” and “hydrolyzed…protein” without the name of the FG-containing ingredient being disclosed.

– Disodium guanylate and disodium inosinate are relatively expensive food additives that work synergistically with inexpensive FG. We believe they would only be used if there was already FG in the product.

– FG will be found in some soaps, shampoos, hair conditioners, and cosmetics, where FG is hidden in ingredients, often with names that include the words “hydrolyzed,” “amino acids,” and/or “protein.”

– Binders and fillers for prescription and non-prescription medications, nutrients, and supplements, may contain FG.

– Enteral feeding materials, and some fluids administered intravenously in hospitals, may contain FG.

– According to the manufacturer, as this was written, Varivax–Merck chicken pox vaccine (Varicella Virus Live), contained L-monosodium glutamate and hydrolyzed gelatin, both of which contain FG. It would appear that most, if not all, live virus vaccines contain some ingredient(s) that contain(s) FG.

– There are a number of ingredients identified as organic that, organic or not, will contain FG. Autolyzed yeast, yeast extract, textured soy protein, and anything hydrolyzed are examples of ingredients that may be made from organic produce but will never-the-less contain FG.

– Drinks, candy, and chewing gum are potential sources of hidden FG. They may also contain aspartame, neotame, Equal, or AminoSweet (one of the newer names for aspartame). We mention aspartame, neotame, and AminoSweet here because they, like MSG, contain a neurotoxic amino acid, and can cause the same reactions that MSG causes.

– Aspartame will be found in some medications, including children’s medications.

– Some waxes used on fruits and vegetables contain FG.

– Anything that breaks down the protein in a product can produce FG as it breaks down that protein. There have been reports of people reacting to meat wrapped in Cryovac.

Cryovac is a registered trademark for a thick plastic in which meat is sealed with the air removed by a vacuum pump. The word Cryovac is also used for the thermoplastic resin wrapping film which can be heat-shrunk onto foods.

– Produce may have been produced using fertilizer or pesticide products that contain FG. Some of these fertilizers may be organic. It is impossible to know from looking at produce whether or not it has been treated with an FG containing fertilizer or pesticide product that leaves residue in or on the produce.

– Some non-organic waxes used on some fruits and vegetables contain FG.

– Additional sources of FG include infant formula, kosher food, enteral feeding products (tube feeding products), dietary supplements, pharmaceuticals, protein drinks often recommended for seniors, protein bars and protein powders, vaccines, personal care products, protein powders sold in health food stores, food that is labeled “organic,” wine, food with labels that say “No Added MSG,” “No MSG Added,” or “No MSG,” food that is falsely advertised as containing no MSG, and in food whose manufacturers claim, in response to questions, that their products contain no MSG.

– FG can be hidden by restaurateurs who claim that the food they serve contains no MSG.

About “organic” products…

Where MSG is concerned, “organic” doesn’t mean “safe.” Ingredients like organic autolyzed yeast and organic natural flavoring have just as much FG in them as those not called “organic.” Following are two products labeled “organic” that were brought to our attention as containing FG. There are others.

Product: Vegetable Bouillon 

By: Morga

Ingredients include: Yeast extract; Maltodextrin

Product: Macaroni & Cheese Dinner

By: Simply Organic

Ingredients include: Natural flavors; Autolyzed yeast extract

Also listed as organic are fertilizer products that contain hydrolyzed fish protein and hydrolyzed chicken feathers. All hydrolyzed ingredients contain FG.

About “Health Food” stores…

Health food stores are mine fields for FG. Protein powders are generally nothing more or less than hydrolyzed proteins – and will contain all three manufactured neurotoxic amino acids: glutamic acid, aspartic acid, and L-cysteine. Food labeled “organic” cannot legitimately contain monosodium glutamate, but can contain other ingredients that contain FG. Dietary supplements will often contain individual amino acids (because they can be absorbed by the body more quickly than amino acids found in protein which have to be digested before they can be absorbed); and if dietary supplements contain individual amino acids, those amino acids may be neurotoxic glutamic acid, aspartic acid, and/or L-cysteine, all manufactured in food and/or chemical plants.

These are the names of some of the FG-containing ingredients often found in Health Food stores:

amino acids (They almost invariably contain glutamic acid.)

autolyzed yeast  

citric acid  


glutamic acid  

hydrolyzed protein  

monopotassium glutamate

monosodium glutamate    


whey protein concentrate

There are also chelates. Minerals found individually and in some multi-vitamins, are usually joined to amino acids for better absorption, i.e., the minerals or multi-vitamins are chelated. The following are names used for chelates that will contain FG and/or aspartic acid and phenylalanine which are two of the main ingredients in MSG’s toxic cousin aspartame:

amino acid chelate (chelated with amino acids)

potassium (or any other mineral) citrate  

potassium (or any other mineral) aspartate   

potassium (or any other mineral) glutamate 

chelated with hydrolyzed protein,  

chelated with protein  

chelated with amino acids

Some supplement manufacturers place asterisks after the names of minerals. Below the list of ingredients, the asterisk is often followed by a note that explains that the mineral is “chelated with hydrolyzed protein,” “chelated with protein,” or “chelated with amino acids.”

Protein powders are all the rage for body builders and older people. The main ingredient is typically a hydrolyzed protein — and hydrolyzed proteins contain FG, excitotoxic aspartic acid (found in aspartame), and excitotoxic L-cysteine (found in some dough conditioners). We have concern for anyone who ingests any form of FG in his or her diet. We have extreme concern for athletes who ingest FG just prior to, just following, or in the course of vigorous exercise, because there is evidence that the adverse effects of FG may be intensified by vigorous exercise. Heart irregularities have been known to be caused by ingestion of FG and/or aspartame. Heart irregularities can result in cardiac arrest.

About hospitals, nursing homes, and extended care facilities…

The most common sources of FG in hospitals, nursing homes, and extended care facilities will be:

-Soups – even if the institution purchases soups and/or soup bases that claim to be MSG-free

-Protein drinks such as Boost and Ensure

-Enteral care products – used when tube feeding



-Salad dressings

-Intravenous solutions. Reactions have been reported to saline solution and solutions containing dextrose. Ringers solution appears to be (or at one time appeared to be) FG-free.

-Anything no fat or low fat

-Anything made with a sugar substitute likely contains neurotoxic aspartame, Equal, or AminoSweet.

People with extreme intolerance to FG have difficulty with pharmaceuticals that contain FG in the binders and/or fillers. They may also react to the starch on powdered gloves and/or the contacts that are glued to a patient’s chest for heart monitoring. The contact points that touch the body may contain guar gum which, after several days’ exposure, may cause adverse reactions.

About pet food…

It’s not only humans that have problems with FG. The first evidence of FG toxicity came from animal studies, some of which demonstrated that animals suffered brain lesions and endocrine disorders when fed monosodium glutamate. The possibility that your animal is sensitive to FG is certainly worth considering. We have received the following from consumers:

Subj: Pet Food & MSG

Date: 8/17/2004 1.48:20 AM Central Standard Time

Dear Folks, would you consider adding an article on MSG in our Pet Food. Just about all the grocery store dog food and most of the canned cat food has various products with an msg base. What can we do about this??? Our pets are much smaller than we are and surely this is extremely bad for their small frame. God help us all. Also, how about my favorite ice cream which is Haagen Daz. I eat the simple flavors, Vanilla, Chocolate, Butter Pecan. I eat it because the original flavors are cream, skim milk, vanilla, chocolate. Anyways, thank you for being here. God Bless your work. M.D.


From: D


Sent: 1/24/2009 2:07:06 P.M. Central Standard Time

Subj: MSG

Our bichpoo dog (6 yrs) ate some sweet & sour pork (left over from Chinese take out). Almost immediately he began to exhibit hyperness, running& jumping, and almost seemed to be “high” on something. He seemed disoriented and didn’t settle down for almost six hours. The vet said he had never seen a dog show these symptoms from eating food. Could he be extremely sensitive to MSG or have you ever heard of this in an animal? Obviously no more people food for Buster. Thanks

Beyond MSG…

People who are sensitive to processed free glutamic acid (MSG), or those who simply would choose to avoid ingestion of toxic amino acids, need to know that there are two other neurotoxic amino acids commonly used in food: aspartic acid and L-cysteine. Aspartic acid is found in the sugar substitutes called “neotame,” “aspartame,” “AminoSweet,” “NutraSweet,” and “Equal.” L-cysteine is identified as L-cysteine and is most often found in dough conditioners.

Eating all your fruits and vegetables?

Eating all your fruits and vegetables and still not feeling as chipper as you used to?  You’ve probably checked the purity of the water you drink and determined that you don’t live over a toxic waste dump.  But have you checked for excitotoxic – brain damaging – free glutamate in the processed foods you’re eating — even ones considered “healthy”?  You’ll find the names of excitotoxic ingredients that are used in food at:

Food for thought

In the treatment of patients with Alzheimer’s disease, are there physicians who take into account the fact that free glutamate, which is known to be involved in neurodegenerative disease, is eaten on a daily basis by people who consume processed food?

There’s nothing mightier than the dollar

Advisers to the U.S. Food and Drug Administration (FDA) recommended, by voice vote of 10 to 4, that the agency approve Pfizer’s respiratory syncytial virus (RSV) vaccine for pregnant women, despite questions about the vaccine’s safety.

During Thursday’s Vaccines and Related Biological Products Advisory Committee meeting, committee members and medical experts raised concerns about premature births identified during Pfizer’s clinical trials.

History tells us that when there’s Big Money involved, there’s nothing unique about the FDA allowing dangerous substances to be administered to adults, children, or even pregnant women. And that doesn’t just apply to drugs.

In 1957, virtually unlimited production of excitotoxic – brain damaging — free glutamate (as in MSG), began, and since that time, consumption of excitotoxic free glutamate in processed and ultra-processed foods has skyrocketed along with explosions in obesity, infertility, Alzheimer’s disease and more, without even a word of caution from the FDA.

We know that when pregnant women consume processed and ultra-processed food they pass brain-damaging ingredients to their fetuses, where it destroys areas of the brain that would have controlled obesity and infertility had they not been obliterated by excitotoxins.

That, however, isn’t something that BIG FOOD and their friends at the FDA will ever admit to.

California: Don’t just cherry-pick toxic food additives to ban!

A new article by Dr. Joseph Mercola reports that California lawmakers are hoping to ban five toxic chemicals used in the manufacture of many processed foods. Combined, the chemicals damage the central nervous system, disrupt the gut microbiome and are linked to hyperactivity in children.

While it’s always a good idea to focus on cleaning up our food supply, why did California stop there? Sure, banning five toxic chemicals used in the manufacture of processed food is great. But what about banning excitotoxic – brain damaging — manufactured free glutamate?  Scientists have known since 1969 that monosodium glutamate contains brain-damaging free glutamate (1).  And now we know that brain-damaging free glutamate is responsible for both the obesity epidemic and the infertility crisis (2). Shouldn’t monosodium glutamate be included in the list of toxic chemicals to be banned instead of being added without restriction to processed food with the blessings of the FDA?

It’s a question we have repeatedly asked the FDA without getting so much as a response. Our research has demonstrated that for over a half-a-century the FDA has served as a pawn of the glutamate industry (3).  The fiction of the safety of MSG and its manufactured free glutamate component was written by the United States manufacturer of MSG, and has been parroted by the FDA to consumers, healthcare professionals, journalists, legislators, foreign health care agencies, the media and those who write “MSG is safe to eat” propaganda, without any one of them raising a question.

Read Dr. Mercola’s article:

Other things in which you might be interested include:

Olney, J. W. Brain Lesions, Obesity, and Other Disturbances in Mice Treated with Monosodium Glutamate. Science. 1969, 164(3880), 719–721. DOI: 10.1126/science.164.3880.719. 

Samuels, A. There are seven lines of evidence leading to the conclusion that the manufactured free glutamate (MfG) in monosodium glutamate is toxic.

Samuels, A. Industry’s FDA

Citizens Petitions to the FDA (click the “download” buttons to view each petition) and please leave a comment at the FDA site!

Samuels, A. (2020) Dose dependent toxicity of glutamic acid: a review, International Journal of Food Properties, 23:1, 412-419, DOI: 10.1080/10942912.2020.1733016

Samuels, A. The Toxicity/safety of Processed Free Glutamic Acid (MSG): A Study in Suppression of Information. Accountability Res. 1999, 6. Accessed Jan/19/2020. 259–310. doi:10.1080/08989629908573933. 

Samuels, A “Glutamic acid: initiator of the obesity epidemic”

Excitotoxic free glutamate eaten by pregnant women and passed to fetuses is responsible for the obesity epidemic.  The Perfect Poison tells it all. Available in both paperback and Kindle editions.

Samuels, A. The Perfect Poison



  1. Olney, J. W. Brain Lesions, Obesity, and Other Disturbances in Mice Treated with Monosodium Glutamate. Science. 1969, 164(3880), 719–721. DOI: 10.1126/science.164.3880.719.
  2. Samuels, A. There are seven lines of evidence leading to the conclusion that the manufactured free glutamate (MfG) in monosodium glutamate is toxic. 
  3. Samuels, A. Industry’s FDA:

If we’d just listened to Dr. Olney in 1969, the obesity crisis would have been stopped in its tracts and there would not be an infertility crisis

Excitotoxic free glutamate delivered to the immature brain of a human kills brain cells in the arcuate nucleus of the hypothalamus causing intractable obesity just as Olney found it caused intractable obesity in animals (Olney, 1969).

Excitotoxic free glutamate delivered to the immature brain of a human kills brain cells in the arcuate nucleus of the hypothalamus causing infertility just as Olney found it caused infertility in animals (Olney, 1969).

There are three conditions needed to produce glutamate-induced brain damage in the arcuate nucleus leading to gross obesity and infertility:

1. An immature brain such as that found in a newborn animal or human fetus,

2. free glutamate in sufficient quantity to be excitotoxic (brain damaging) – available since 1957 when the U.S. producer of free glutamate began mass producing free glutamate for use in flavor-enhancers, and

3. a way to deliver the required large quantity of free glutamate to the immature brain.

For delivery to animals, researchers administered glutamate via free feeding, injection and/or some form of force feeding such as gavage.

For delivery to humans, pregnant women who consume large quantities of free glutamate in processed and ultra-processed foods deliver it across the placenta via the umbilical cord to the arcuate nucleus of the fetal brain where it destroys brain cells that would have regulated appetite, satiety and reproductive function had they not been destroyed. (NOTE: The circumventricular organs among which the arcuate nucleus is found, lie outside of the blood-brain barrier and, therefore, are not protected by the blood-brain barrier.)


Olney, 1969. Olney JW. Brain lesions, obesity, and other disturbances in mice treated with monosodium glutamate. Science. 1969 May 9;164(3880):719-21. doi: 10.1126/science.164.3880.719. PMID: 5778021.

Autism, Asperger’s and Parkinson’s were rarities before 1957

1957 was the year that mass produced free glutamate was first consumed by pregnant women, causing brain damage followed by irreversible obesity in their fetuses. 

1957 was the year that Lucas and Newhouse demonstrated that manufactured free glutamate (the toxic component of monosodium glutamate) damaged the inner layers of the retina, causing macular degeneration.

I957 was the year that the major U.S. producer of MSG and the free glutamate contained in it started producing free glutamate in sufficient amounts to cause that free glutamate to be excitotoxic – brain damaging.

Prior to 1957, there was not very much in the way of free amino acids to be found in food in the American diet, and ultra-processed food hadn’t been invented.

Prior to a 1957 change in glutamate production, it would have been rare for there to be enough free glutamate in food to cause it to be excitotoxic – brain damaging.

Today there’s more than enough free glutamate to become brain damaging if multiple servings are consumed during the course of a day.

Glutamic acid.  On the one hand, it’s essential to life itself, but in 1957 it became a deadly killer. 

Monosodium glutamate, the food additive, was invented in 1908 at which time the glutamate component was produced by extracting glutamate from protein — a slow and costly method.

It was reinvented in 1957 using genetically modified bacteria to produce glutamate. Following reinvention, virtually unlimited amounts of free glutamate became available, and great quantities of free glutamate, often in monosodium glutamate, were poured into processed foods.  For the first time in history, there existed the excessive amounts of free glutamate needed to produce excitotoxicity.

In 1968, John Olney published the first of many studies that demonstrated that large (excessive) amounts of glutamic acid delivered in monosodium glutamate destroyed neurons in the arcuate nucleus of the hypothalamus, destroying the subject’s capacity for managing appetite and satiety, and also destroying neurons essential to reproductive function (fertility).

In the 1970s, Olney and others established that immature animals fed large amounts of free glutamate suffered brain damage followed by intractable obesity, behavior disturbances, and/or reproductive disorders including infertility

By 1980, glutamate-associated disorders such as headaches, asthma, diabetes, muscle pain, atrial fibrillation, ischemia, trauma, seizures, stroke, Alzheimer’s disease, amyotrophic lateral sclerosis (ALS), Huntington’s disease, Parkinson’s disease, depression, multiple sclerosis, schizophrenia, obsessive-compulsive disorder (OCD), epilepsy, addiction, attention-deficit/hyperactivity disorder (ADHD), frontotemporal dementia and autism were on the rise, and evidence of the toxic effects of glutamate were generally accepted by the scientific community.

The obesity epidemic was set in motion following the 1957 introduction of unlimited amounts of excitotoxic –brain damaging — free glutamate in processed foods, dietary supplements, snacks, protein powders and protein drinks, protein substitutes, enteral care products, and pharmaceuticals. 

In 2022 Samuels demonstrated that the abnormalities first seen in 1969 by Olney in animals fed free glutamate were being replicated in humans. This happens when a pregnant woman ingests large amounts of free glutamate and “shares” it though the umbilical cord with her fetus.

It’s only since 1957 that manufactured free glutamate has been a deadly killer.