MSG - Monosodium Glutamate

EXCITOTOXINS AND THE DEVELOPING BRAIN

Recognizing the immediate danger to the public, especially to the unborn child, Dr. Olney and others testified before Congress concerning these dangers. As a result of their vigilance, MSG was voluntarily removed from baby foods in 1969.

But no one had warned pregnant women of the danger to their developing babies caused by the MSG found within their own food. This danger would exist if the glutamate from the mother’s blood entered the blood of their unborn baby. In 1974 Dr. Olney demonstrated that MSG, when fed to pregnant Rhesus monkeys, could cause brain damage to their offspring. [18] Other researchers found similar results when pregnant rats were fed MSG. [19] Yet millions of pregnant women continued to eat foods laced with MSG and other equally potent excitotoxins while the FDA remained silent. And gynecologists and pediatricians were not told to warn their patients of this real danger.

After birth and following weaning from bottled or breast milk, most mothers begin feeding their babies food from the table. These foods frequently contain large amounts of MSG and hydrolyzed vegetable protein. Dr. Olney found that these children were receiving doses of MSG from the table food that equaled the dose used experimentally to produce severe brain cell destruction in animal experiments. By that I mean proportionally equal. Often, critics of this observation claim that humans rarely receive such high doses. This is just not true. Incredibly, humans develop higher blood levels of glutamate following ingestion of MSG than does any other animal species known. [20] Dr. Olney noted that:

The amount of MSG in a single bowl of commercially available soup is probably enough to cause blood glutamate levels to rise higher in a human child than levels that predictably cause brain damage in immature animals. [21]

When adult humans are fed 100 to 150 milligrams per kilogram of body weight of MSG, their blood levels rise twenty times higher than normal as compared to a four-fold rise seen in experimental mice fed a comparable dose. Monkeys develop a zero-fold rise in blood glutamate after similar doses of glutamate. We know that children are frequently exposed to doses of MSG and other related excitotoxins in their food in extremely high doses. But the fact that humans concentrate glutamate in their blood to a greater degree than other animal species means that the parts of the human infant’s brain not protected by the blood-brain barrier is exposed to even higher doses following MSG or hydrolyzed vegetable protein ingestion than is used experimentally to produce brain damage in animals.

And, it should be noted, the child’s brain is four times more sensitive than is the adult brain to these toxins. [22] A survey of children’s diets indicated that they often consume the same amounts of MSG as adults. This is especially true with the large number of junk foods and fast foods containing massive amounts of MSG and other excitotoxin taste enhancers, such as chips, frozen dinners, canned pasta, and diet drinks (containing aspartate).

When my own children were small toddlers, my wife and I were amazed at how much they loved a special canned pasta dish called ABCs and 1-2-3s by Chef Boyardee. These are little pasta alphabet letters and numbers in a mixture of tomato sauce. Our children wanted it for every meal. Once I became aware of the danger of MSG, I discovered that this delicious meal-in-a-can contained both MSG and hydrolyzed vegetable protein. No wonder they loved it! We began to examine our children’s food and discovered that many foods specifically advertised for children contained large doses of such excitotoxin taste enhancers.

Dr. Olney astutely pointed out the irony of this food industry practice:

Thus, today we are witnessing an ironic situation; while knowledgeable neuroscientists are fervently attempting to develop methods protecting CNS [brain] neurons against neurotoxic potential of endogenous Glu [glutamate] and Asp [aspartate], other elements of society are vigorously promoting the unlimited use of exogenous Glu and Asp as food additives. [23]

Today the experimental evidence demonstrating the neurotoxic potential of these excitotoxins is so overwhelming, as can be seen from the scientific citations in this book, that it can no longer be ignored.

(...)

 Both glutamate and aspartame can cause neurons to become extremely excited and, if given in large enough doses, they can cause these cells to degenerate and die. It is for this reason that the nervous system carefully controls the concentration of these two amino acids in the fluid surrounding the neurons (called the extracellular space). It does this by several methods, the most important of which is a system designed to remove any excess glutamate from this extracellular space. This is accomplished by a special pumping system that transfers the excess glutamate back into surrounding glial cells. (FIG 3-2) Glial cells surround the neurons and supply them with energy. This pump acts like a bilge pump on a ship. If the pump fails the ship fills up water and sinks. Normally, the glutamate clearing system is very efficient. This is one possible reason why experimentally it takes higher doses of MSG to fatally damage the neurons of adult animals than infant animals–the adult glutamate system may be more competent. But remember, even small doses can damage these neurons without actually killing them.

While this pumping system is very effective, it requires an enormous amount of cellular energy (in the form of the energy molecule ATP, or adenosine triphosphate) for its operation. It is sort of like the old-time fire brigade, where a line of people hoisted buckets down a human chain to put out a fire. It required a lot of energy on the part of the people making up the bucket brigade. If they ran out of energy the fire would rage out of control. The same thing happens when energy production is reduced in the brain: the protective pumps begin to fail and glutamate begins to accumulate in the around the neuron, including in the area of the synapse. If the energy is not restored the neurons, in essence, will burn up–they are literally excited to death.

from: EXCITOTOXINS The Taste that Kills

HOW MONOSODIUM GLUTAMATE, ASPARTAME (NUTRASWEET®), AND SIMILAR SUBSTANCES CAN CAUSE HARM TO THE BRAIN AND NERVOUS SYSTEM AND THEIR RELATIONSHIP TO NEURODEGENERATIVE DISEASES SUCH AS ALZHEIMER’S, LOU GEHRIG’S DISEASE (ALS) AND OTHERS.

Russell L. Blaylock, MD