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Excitotoxins...tasty but deadly

Article written by Kaye Sehm, posted

Excitotoxins...tasty but deadly

A special report from the book Excitotoxins: The Taste that Kills by Dr Russell Blaylock

What if someone were to tell you that a chemical added to food could cause brain damage in your children, and that this chemical could affect your children's nervous systems through their entire life so that in later years they may have learning or emotional difficulties? What if there was scientific evidence that these chemicals could damage a critical part of the brain known to control hormones so that later in life your child might have endocrine problems? How would you feel?

Suppose evidence was presented to you strongly suggesting that the artificial sweetener in your diet soft drink may cause brain tumours to develop, and that the number of brain tumours reported since the widespread introduction of this artificial sweetener has risen dramatically? Would that affect your decision to drink these products and especially to allow your children to drink them? What if you could be shown overwhelming evidence that one of the main ingredients in this sweetener (aspartate) could cause the same brain lesions as MSG? Would that affect your buying decisions?

And finally, what if it could be demonstrated that all of these types of chemicals (called excitotoxins) could possibly aggravate or even precipitate many of the neurodegenerative brain disorders such as migraines, seizures, infections, abnormal neural development, certain endocrine disorders, specific types of obesity as well as the neurodegenerative diseases such as Parkinson's disease, Huntington's disease, ALS, and Alzheimer's disease? Would you be concerned if you knew that these excitotoxin food additives are a particular risk if you have ever had a stroke, brain injury, brain tumour, seizure, or have suffered from hypertension, diabetes, meningitis or viral encephalitis?

We would all be more than just concerned to learn that well known powerful brain toxins were being added to our food and drink to boost sales. We would be especially upset to learn that these additives have no other purpose than to enhance the taste of food and the sweetness of various diet products.

You would also be upset to learn that many of these brain lesions in your children are irreversible and can follow a single exposure of a sufficient concentration. And I would bet that you would be amazed to learn that the food industry disguises many of these "excitotoxin additives" so that they will not be recognized. In fact, many foods that are labelled "No MSG" not only contain MSG, but also contain other excitotoxins of equal potency.


For thousands of years Japanese cooks have added a special ingredient to their recipes to magnify the desired taste of foods. This ingredient was made from a sea weed known as "sea tangle" or kombu. In 1908 the active chemical of this "taste enhancing" ingredient was isolated. Most of you will immediately recognize the chemical which has this almost magical property it's called monosodium glutamate, or MSG. It had the ability to make ordinary or tasteless food into something very tasty.

It was then turned into a worldwide multimillion dollar industry. At the centre of this empire is the Ajinomoto Company which today produces most of the world's supply of MSG and a related taste-enhancing substance called hydrolyzed vegetable protein, which also contains MSG.

After World War II, American food manufacturers discovered why the rations of the Japanese soldiers tasted so good. They decided to put this tasteenhancing substance into their foods. Soon all of the giant food manufacturers were adding millions of pounds of MSG each year to processed foods. At the time of its discovery, it was thought to be perfectly safe, since it was a natural substance - it is an amino acid which are used to create proteins.

Dangers discovered

The amounts of MSG and similar additives being added to foods increased throughout the post-war period. In fact, the amount of MSG alone added to foods has doubled in every decade since the 1940's. By 1972 262,000 metric tons of MSG were produced. Throughout this period, few suspected that these taste enhancing additives could be doing serious harm to individuals eating these foods. But, by the end of the 1960's, research data began to appear demonstrating the dangers of MSG as a food additive. This scientific data should have alerted those responsible for public safety to the danger. Excitotoxins are now found in almost all processed foods. In many cases they are being added in disguised forms, such as natural flavourings, spices, yeast extract, textured protein, soy protein extract etc. It is also known that given in liquid forms, as what occurs in soups, gravies, diet soft drinks they are more toxic than when added to solid food. This is because they are more rapidly absorbed and reach higher blood levels.

What is an excitotoxin?

These are substances, usually amino acids that react with specialized receptors in the brain in such a way as to lead to the destruction of certain types of brain cells. Glutamate is one of the more common known excitotoxin. MSG is the sodium salt of glutamate. This amino acid is a normal transmitter in the brain. In fact it is the most commonly used neurotransmitter in the brain. What makes it dangerous is the amount received by the brain. When received in higher concentrations the cells undergo a process and eventually die.

The brain has mechanisms to stop the build-up of MSG in the brain. This is called the blood brain barrier, a system that slows the glutamate entry into the brain cells. But this system was designed to protect against occasional elevation of glutamate. It was not designed to eliminate the high doses of glutamate and/or aspartame consumed daily. The glutamate will by-pass this barrier and enter the brain in toxic concentrations and literally excite the brain cell until it dies.

Until this time, neuroscientists assumed that glutamate supplied the brain with energy. Based on this idea scientists in one clinical study, fed large doses of MSG to retarded children to see if it would improve their IQ. The experiment failed. Then, in 1957, two ophthalmologists, Lucas and Newhouse, decided to test MSG on infant mice in an effort to study an eye disease known as hereditary retinal dystrophy. But, when they examined the eye tissues of the mice, they made a startling discovery. The MSG had destroyed all of the nerve cells in the inner layers of the animal's retina which are the visual receptor cells of the eye.

Despite this frightening discovery, MSG continued to be added to food in enormous amounts and cookbooks continued to recommend it as a taste enhancing additive for recipes. But the worst was yet to be disclosed about this compound. Some ten years later John W. Olney, MD, a neuroscientist working at the Department of Psychiatry at Washington University in St. Louis, repeated Lucas and Newhouse's experiment in infant mice. He found that MSG was not only toxic to the retina, but also to the brain. When he examined the animals' brains he discovered that specialized cells in a critical area of the animals' brain, the hypothalamus, were destroyed, after a single dose of MSG.

The implications of Dr. Olney's findings should have been earth-shaking to say the least. Why? Because millions of babies all over the world were eating baby foods containing large amounts of MSG and hydrolyzed vegetable protein (a compound which contains three excitotoxins). In fact, the concentrations of MSG found in baby foods was equal to that used to create brain lesions in experimental animals. And in all of these experiments, immature animals were found to be much more vulnerable to the toxic effects of MSG than were older animals. This was true in all animal species tested.

Yet, food manufacturers continued to add tons of this excitotoxic additive to foods of all kinds, including baby foods. Even the government's public health watchdog agency, the Food and Drug Administration, refused to take action. Dr. Olney, one of the leading researchers in this area, felt compelled to do something to protect unsuspecting mothers and their infants from this danger. First he informed the FDA of the real danger to human infants and encouraged them to take action. But they refused. His only recourse was to go public with what he knew to be true that MSG was a dangerous compound that should not be added to infant foods. It was only after his testimony before a Congressional committee that the food manufacturers agreed to remove MSG from baby foods. But did they really?

Hydrolized vegetable protein more dangerous than MSG

Instead of adding pure MSG they added a substance known as hydrolyzed vegetable protein that contains three known excitotoxins and has added MSG. This substance is even more dangerous than MSG. They continued this practice for seven more years, and there is evidence that excitotoxins are still added to baby foods today. Usually these are in the form of caseinate, beef or chicken broth, or flavouring. Another type of food sold by these manufacturers is directed at toddlers. At least some of these foods contain hydrolyzed vegetable protein. Experimentally we know that the brain is extremely vulnerable to excitotoxins even at this early stage of development.

Glutamate and other excitotoxins can alter the way the brain is formed during development. It is hypothesized by some neuroscientist that exposure to these powerful compounds early in life can cause developmental brain defects that would produce learning difficulties and behavioural problems as the child grows older. There is also some evidence that it may contribute to violent behaviour as well.

In experimental animals "MSG babies" are found to be short in stature, obese, and to have difficulty reproducing. This effect only becomes evident long after the initial MSG exposure. More detailed studies have found that "MSG babies" have severe disorders involving several hormones normally produced by the hypothalamus. Not only do we have an obesity epidemic today, but most everyone has problem with hormonal imbalance.

Unfortunately, MSG is not the only taste enhancing food additive known to cause damage to the nervous system. In fact, there is a whole class of chemicals that can produce very similar damage they all share one important property. When neurons are exposed to these substances, they become very excited and fire their impulses very rapidly until they reach a state of extreme exhaustion. Several hours later these neurons suddenly die, as if the cells were excited to death. As a result, neuroscientists have dubbed this class of chemicals "excitotoxins".

"Natural flavourings" may contain 20-60% MSG

Several of these "excitotoxins" are manmade and are used as research tools. Others are found in nature, such as glutamate, aspartate and cysteine all of which are amino acids. MSG is a modified form of glutamic acid in which sodium is added to the molecule. But the toxic portion is the glutamic acid, not the sodium. Often food manufacturers will mix MSG with other substances to disguise it, or use substances known to contain high concentrations of glutamate and/or aspartate. For example, the label designation "natural flavouring" may contain anywhere from 20 to 60 percent MSG.

How hydrolized vegetable protein is made

This powerful excitotoxin mixture is often portrayed as a perfectly safe and "natural" substance. "After all," manufacturers say, "it's made from plants." Actually, this mixture is made from "junk" vegetables that are unfit for sale. They are especially selected so as to have naturally high contents of glutamate. The extraction process of hydrolysis involves boiling these vegetables in a vat of acid. This is followed by a process of neutralization with caustic soda. The resulting product is a brown sludge that collects on the top. This is scraped off and allowed to dry. The end product is a brown powder that is high in three known excitotoxins glutamate, aspartate, and cystoic acid (which converts in the body to cysteine). It is then added by the food industry to everything from canned tuna to baby food. Hydrolyzed vegetable protein should not be confused with hydrolyzed vegetable oil. The oil does not cantain any concentration of glutamate, it is an oil.

So what is it that these "excitotoxins" actually do that is so important to the food manufacturers? All of these chemicals stimulate the taste cells in the tongue, thereby greatly enhancing the taste of whatever food to which it is added. It is what gives soups the scrumptious taste that we all love so much. Today they are used extensively in sauces, soups, gravy mixes, and especially frozen diet foods. Low fat foods are often tasteless. To help sell them to the public, food manufacturers add "excitotoxin" taste enhancers to these foods to improve the taste.

But the negative effects of excitotoxins are not limited to small children. There is growing evidence that excitotoxins play a major role is a whole group of degenerative brain diseases in adults especially the elderly. These diseases include Parkinson's disease, Alzheimer's disease, Huntington's disease, MS, Amyotrophic Lateral Sclerosis (ALS), as well as several more rare disorders of the nervous system.

What all of these diseases have in common is a slow destruction of brain cells that are specifically sensitive to excitotoxin damage. Neurons that use glutamate for a transmitter are destroyed by these high concentrations of glutamate, while other neurons that use other transmitters are spared. While there is little evidence that food borne excitotoxins are the cause of these disorders, there is growing evidence that they can aggravate these conditions and that they may even precipitate them in sensitive individuals. Certainly the scientific evidence is far too strong to ignore the possibility that excitotoxic food additives may cause such conditions to appear sooner and to a more serious degree. For those who suffer from these diseases it is best to avoid all food containing MSG as well as meat, cheeses and pureed tomatoes which all have high levels of glutamate.

More and more diseases of the nervous system are being linked to excitotoxin build-up in the brain. For example disorders such as strokes, brain injury, hypoglycemic brain damage, seizures, migraine headaches, hypoxic brain damage, and even AIDS dementia have been linked to excitotoxin damage. There is also evidence that some individuals born with metabolic defects in certain brain cells may be particularly susceptible to excitotoxin damage.

In his book, Dr Blaylock has tried to compile some of the vital research linking excitotoxins to injury and diseases of the nervous system. This area of research is growing by leaps and bounds. He feels that this new information linking excitotoxins with disease must reach the general public so that we can make up our own mind on this issue. Unfortunately, most of this critical information is buried in technical and scientific journals, far from the public's eye.

His book is written mainly for the lay public, but also for those trained in medical science and biology. He has provided references for those who seek either to check the accuracy of his statements or to delve deeper into the subject themselves. Of course, the book does not claim to be an exhaustive study of each area of controversy, but leading experts are quoted in each case. The field is far too vast for such a review.

He was warned when he submitted the manuscript for the book to his publisher that he should prepare for the backlash from the food industry, and especially from the representatives of the glutamate manufacturers. These two industries have joined together to fight anyone who would dare criticize the use of flavour enhancers. In fact, they have formed a special lobby group to counter any negative claims about their product. This group, called The Glutamate Association, is made up of representatives of major US food manufacturers and the Ajinomoto Company, which, based in Japan, is the chief manufacturer of MSG and hydrolyzed protein. Many have been scared off by these powerful businesses and organizations. But Dr Blaylock feel that the message is too important to be left alone. The FDA has failed in its stated purpose of protecting the public from harmful substances being added to the food supply. Millions of lives are at stake including those of future generations. People must be warned.

A growing list of excitotoxins is being discovered, including several that are found naturally. L- cysteine is a very powerful excitotoxin and is added to certain bread dough as well as being sold as a supplement. Homocysteine is also an excitotoxin.

Additives that always have excitotoxins.

Always check ingredient lists.
Monosodium glutamate
Hydrolyzed vegetable protein
Hydrolyzed protein
Hydrolyzed plant protein
Plant protein extract
Sodium caseinate
Calcium caseinate
Yeast extract (vegemite, marmite etc)
Textured protein
Autolyzed yeast
Hydrolyzed oat flour
Additives that may have excitotoxins
Malt extract
Malt flavouring
Natural flavouring
Natural beef or chicken flavouring


Another excitotoxin additive that is familiar to all of us is the artificial sweetener NutraSweet, also known under other brand names. Actually, 50 percent of the compound is composed of the excitotoxin aspartate. Like glutamate, aspartame acts in the same way as glutumate killing brain cells by allowing too much calcium into the cell. This triggers excessive amounts of free radicals which kill the cells. NutraSweet is used in many diet foods and beverages. It is well recognized that liquid forms of excitotoxins are much more toxic to the brain than dry forms as they are absorbed faster and produce higher blood levels than when mixed with solid foods.

Aspartame is made up of three chemicals: aspartic acid, phenylalanine and methanol. Aspartic acid is a powerful excitotoxin - it is as powerful as glutamate. Phenylalanine causes mental retardation in children, emotional disorders such as depression, schizophrenia and makes one susceptible to seizures. Methanol is a wood alcohol that is a deadly poison. It is methanol that causes skid row alcoholics to end up blind or dead. It is broken down to formic acid (what causes fire ant stings) and formaldehyde (a deadly neurotoxin). Symptoms of methanol poisoning include headaches, ear buzzing, dizziness, nausea, gastrointestinal disturbances, weakness, vertigo, chills, memory lapses, numbness and shooting pains in the extremities, behavioural problems and neuritis. The most well known problem from methanol poisoning are vision related including misty vision, blurring of the vision, retinal damage and blindness.

This is found in many beverages and foods today. Especially dangerous are the so called diet drinks. The American troops who were in Iraq during Desert Storm drunk large amounts of aspartame sweetened beverages that had been heated up in the hot Saudi Arabian desert sun (heated beverages containing aspartame are even more hazardous). Many of the troops returned home with numerous disorders similar to what has been seen in persons who have been chemically poisoned by formaldehyde.

Diketopiperazine (DKP) is a by product of aspartame metabolism that has been implicated to brain tumours. The more aspartame was consumed, the more tumours would develop. Other studies link aspartame to birth defects, Multiple Sclerosis, uterine and ovarian cancer. Dr Blaylock says that aspartame can precipitate diabetes in persons who are genetically susceptible to diabetes. The Air Force has published articles that warn pilots who consume aspartame that it can make the pilots more susceptible to seizures and vertigo. Over 600 pilots have reported symptoms including some who have reported suffering grand mal seizures in the cockpit due to aspartame.

Aspartame can be found in many different products. Always check the labels.


Excitotoxins affect everyone who is eating any processed foods. The only way to avoid these is by carefully selecting fresh vegetables and fruit and making almost everything from scratch. Some people may say that they are not sensitive to MSG, but this is a mistake. The destructive effect of MSG and related compounds is not an allergic reaction, it is a toxic reaction that occurs in virtually everyone. Some are more sensitive than others, but all are affected. The symptoms can remain silent for years.

Today there are many epidemics of unexplained diseases. I believe that it is highly probable that some of them are linked to excitotoxins. A very obvious one is the obesity epidemic. For those of us who are old enough can remember back to the time when many people were actually thin. In laboratory tests, mice given excitotoxins become obese. Another study showed mice exposed to MSG developed diabetes. The list goes on and on. The increase in brain tumours corresponds to the time when aspartame was introduced.

How do we protect ourselves against any more damage from excitotoxins. Dr Blaylock goes into more detail in his book. In a nutshell - we must avoid anything with excitotoxins and have a well balanced and healthy diet. Magnesium is the most powerful protectant to the brain. Leafy plants are high in magnesium. So eating a healthy diet is the best way to minimise damage.

Dr Russell Blaylock is a board-certified neurosurgeon, an assistant professor at the University of Mississippi, has written medical textbooks as well as having a busy neurosurgical practice. He noticed that patients in their twenties were complaining about their inability to remember things. He systematically documents a detailed and well researched argument that certain substances added to foods and beverages literally stimulate neurons to death, causing brain damage of varying degrees.

Article written by Kaye Sehm, posted with permission.