DANGER! NOT JUST TASTE ENHANCERS1
by George E. Shambaugh, Jr., MD, Professor Emeritus of Otolaryngology, Northwestern University Medical School, graduate of Harvard University Medical School, author of three editions of Surgery of the Ear, as well as approximately 400 articles and editorials in medical journals
In Japan in 1908 a chemist trained in Germany was looking for the substance in Kombu seaweed that enhances the taste of food and discovered MSG (monosodium glutamate). By 1933 Japanese cooks were using over 10 million pounds of it to make bland recipes taste better. In 1948 quartermasters in the American army met with the foremost food manufacturers in the United States to discuss the Japanese technique for improving the taste of almost any food, and MSG use in America increased rapidly. Today it is added to most soups, chips, fast and frozen foods, prepared packaged dinners, and canned foods. However, since the public has learned about the syndrome of undesirable symptoms produced by MSG, food manufacturers often disguise it as "vegetable protein," "natural flavoring," or "spices," each containing12 to 40 percent MSG. Other commonly used taste enhancers are aspartame (NutraSweet®), cysteine, and aspartic acid. All of them enhance the taste of foods and beverages to which they are added by exciting the taste cells on the tongue.
There is increasing scientific evidence, however, that taste cells on the tongue are not the only things that these taste enhancers stimulate. When neurons in the brain are exposed to these substances, they become very excited and fire their impulses 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."
Dr. Russell Blaylock, a neurosurgeon, has compiled some of the vital research linking excitotoxins to injury and diseases of the nervous system. "Unfortunately," says Blaylock, "most of the information has been buried in technical and scientific journals, far from the public eye." His book, Excitotoxins: The Taste That Kills, 2 published in 1994, cites 430 such articles.
Dr. Blaylock relates how two ophthalmologists in 1957 fed MSG to baby mice and found that the nerve cells of the retina were destroyed by this taste enhancer. Ten years later another neuroscientist at Washington University, Dr. John W. Olney, repeated the experiment of giving MSG to baby mice. He found that not only were the retinal neurocells destroyed, but brain cells in the hypothalamus were also destroyed after a single dose of MSG. Dr. Olney, knowing that MSG was being added to baby food, informed the United States Food and Drug Administration (FDA) of his findings, but failed to obtain any interest or action. He and others then went directly to Congress, testifying before a Congressional committee. The committee was sufficiently impressed to persuade baby food manufacturers to remove MSG from their products in 1969. But no one warned pregnant mothers to avoid MSG in their own food.
Continuing his research, Dr. Olney demonstrated in 1974 that when MSG was fed to pregnant Rhesus monkeys it could cause brain damage to their offspring. Other researchers found similar results when pregnant rats were fed MSG. Yet the FDA remained silent, and gynecologists and pediatricians were not told to warn their patients of this danger. Critics of Olney’s research claim that humans rarely ingest the high doses of MSG given to baby mice and pregnant monkeys. On the contrary, in humans those excitotoxins are concentrated five times more than in experimental animals. The child’s brain is four times more sensitive to any toxins than is an adult’s.
The human brain, when fully developed, contains one hundred billion neurons, with trillions of fiber connections between them. The development of these connections between neurons requires stimulation of the body by touch, speech, and vision. (Unstimulated babies left undisturbed in their cribs are delayed in their ability to sit up and to walk.) But overstimulation, as well as understimulation, can be devastating on brain development.
Since we cannot experiment on human children, we must rely upon animal experimentation to learn the effects of substances that are potential health hazards. Baby mice fed MSG, for instance, grow up to be short and grossly obese despite dietary intake in normal amounts for mice. (Today obesity is a growing health problem. Could this be related to the heavy consumption of the so-called "diet sodas" containing NutraSweet®, which actually promote obesity due to the effects of the excitotoxin?)
We know that the hypothalamus is very immature at birth. The damage to this structure of the brain by MSG leads to severe endocrine problems later in life, among them decreased thyroid hormone, increased tendency toward diabetes, and higher cortisone levels than normal. A question that will be raised is: Are children receiving enough excitotoxins to damage their hypothalamus? They may be. A child consuming a soup containing MSG plus a drink with NutraSweet® will have a blood level of excitotoxins six times the blood level that destroys hypothalamus neurons in baby mice. The younger the child, the greater the danger to the brain.
There are researchers who report that MSG has no adverse effect on hypothalamic function. Dr. C. B. Neineroff, a primary researcher in this field, attempted to get samples of animals purported to show no neural damage from MSG. Every time, he was denied such requests. (Why?)
While small children are more vulnerable to the effects of excitotoxins, there is increasing evidence that those adults who are especially sensitive to them suffer a slow destruction of brain cells. Previous traumas to the brain, as from a fractured skull, brain concussion, or previous illnesses affecting the brain (such as an attack of encephalitis or exposure to chemical toxins that affect the brain), increase vulnerability to degeneration from excitotoxins. The elderly, whose tissues have suffered the wear and tear of previous illnesses and physical trauma over the years, are especially vulnerable to excitotoxin damage. While there is little evidence that food-borne excitotoxins are the only cause of Parkinson’s, Alzheimer’s, Huntington’s disease, and amyotrophic lateral sclerosis (ALS, Lou Gehrig’s disease), there is evidence that in excess they can aggravate these conditions, and may even precipitate them in sensitive individuals.
In human children and adults not all neurons are affected equally by excitotoxins, for if they were, the child or adult would soon die. Instead, the delayed loss of a neuron here and a neuron there may occur over a considerable period of months or years before there begins to be impairment of function. Other toxic substances in addition to excitotoxins accelerate the death of individual neurons. Mercury, lead, aluminum, and cadmium are pollutants to which all of us are exposed in varying concentrations and over many years. An example is lead poisoning in children, which causes sufficient damage to brain neurons to permanently impair the child’s learning ability. Excitotoxins in beverages and foods will increase the damage to the brain of lead-poisoned children.
The mode of action of excitotoxins on an individual neuron has been shown to weaken the membrane that surrounds each living cell. While exciting the neurons to fire repeatedly, the excitotoxin allows calcium to enter the cell through its membrane. This causes the production of free oxygen radicals, which are believed to be the central cause for every injury and disease, including arthritis and cancer. Fortunately, the normal healthy body possesses antioxidants to quench free radicals before they cause serious damage. Vitamin C in water, and vitamin E and co-enzyme Q10 in fat, help to quench free radicals. In addition, the healthy and adequately nourished body produces three enzymes that trap and neutralize free radicals: superoxide dismutase, glutathione peroxidase, and catalase. These enzymes require magnesium, chromium, zinc, copper, and selenium. All of these essential nutrients are marginally deficient in today’s American diet of processed foods, so they need to be supplied as supplements.
If, indeed, excitotoxins such as MSG (disguised as "vegetable protein," "natural flavoring," or "spices") and aspartame (NutraSweet®) cysteine and aspartic acid may be damaging the brains of children and adults, why is the public not being informed? Dr. Olney found when he published his research in 1969 on how MSG and similar substances could damage the brains of children that there was a firestorm of criticism, with a multitude of papers claiming that experiments in other labs found no toxicity for MSG. Olney found that nearly all such studies were affiliated with and paid for by the food industry. When he testified before a government sponsored "food protection committee," a spokesman from the food industry testified that "even if MSG destroys the arcuate nucleus in the hypothalamus, this doesn’t matter because it was not known to have any significance." Yet, it was already well known then that the arcuate nucleus regulates the release of essential hormones by the pituitary! This "food protection committee" ignored Dr. Olney’s research and believed the biased reports of the food industry. Dr. Olney concluded that the FDA, supposedly protecting the public, is clearly dominated by powerful and well-heeled industrial giants.
Alzheimer’s disease does appear to be increasing beyond the normal rate of aging. The evidence that Alzheimer’s deterioration is associated with high levels of excitotoxins in the brain, and that there is a strong family history of this disease, indicates that those having had a stroke, high blood pressure, or brain trauma should restrict or totally avoid foods containing MSG, aspartame, and similar substances.
Since free oxygen radicals play a major role in the ultimate brain damage, my advice is to take adequate vitamin C (four to six grams a day in divided doses), vitamin E, (400 to 800 International Units), and beta carotene, 60 milligrams a day in divided doses. The minerals zinc, selenium, and magnesium, deficient in the usual American diet, need to be supplemented: zinc picolinate, containing 20 milligrams of elemental zinc, twice daily; copper sulphate, with 5 milligrams of elemental copper, once daily; selenium, 200 micrograms twice daily; and magnesium, 500 milligrams twice daily to assist the body to produce superoxidase dismutase, glutathione peroxidase, and catalase.
To strengthen the immune system, take cold-pressed flaxseed or linseed oil, one or two tablespoons daily, and a diet with plenty of complex carbohydrates, plus avoidance of refined sugar to reduce hypoglycemic episodes. Regular exercise by walking one to three miles daily will help to normalize blood-sugar levels. Avoid drinking more than two cups of coffee daily.
Incidentally, just as Excitotoxins was going to press it was learned by Dr. Blaylock that excitotoxins are being added to cigarettes to enhance their taste. "The Taste That Kills," indeed!
1This article was first published in the Summer1995 Shambaugh Medical Research Institute Newsletter #45. Dr. Shambaugh has kindly given us his permission to publish it again in NOHA NEWS.
2Excitotoxins: The Taste That Kills by Russell L. Blaylock, MD, copyright 1994, Health Press, Box 1388, Santa Fe, New Mexico, 87504, 264 pages, hard back, $27.00.
Article from NOHA NEWS, Vol. XXI, No. 3, Summer 1996, pages 2-4.