Date: Thu, 10 Aug 2000 To: Bettym19@pop.mindspring.com From: "Russell Blaylock, M.D." Subject: Hypothalamus Aspartame, MSG and other Excitotoxins and the Hypothalamus The hypothalamus is a small area of the brain, no larger than the fingernail, that despite its small size, is responsible for controlling some of the most vital neural systems in the body. The wiring of the hypothalamus is some of the most complex in the nervous system, with connections not only to the pituitary, but also to the limbic system (emotional control system), hippocampus, striatum and brain stem. Through these connections it regulates emotions, autonomic control ( parasympathetic and sympathetic), hunger and satiety, immunity, memory input, and anger control. Disruptions in this vital piece of brain can result in anything from minor behavioral problems or endocrine malfunctions to major disruptions in sexual functions, obesity, immune suppression and endocrine gland failure. Newer findings indicate that the hypothalamus is involved in several endocrine syndromes, neurological diseases and even psychiatric disorders. As early as 1976, it was shown that aspartame feeding in mice could produce lesions in the hypothalamus of newborns. It should be realized that these are lesions (injuries) that can be seen through an ordinary light microscope. While the lesions produced by aspartame doses equiavlent to MSG will produce smaller lesions, they are significant none the less. Defenders of the safety of aspartame and MSG often report studies that have shown no damage to the hypothalamus when seen under the light microscope. Several studies have shown that the neurons can be injured without such visible physical damage being present. The effects may be physiological and biochemical without physical changes in the neuron. Within the hypothalamus there are a number of collections of neurons called nuclei. The arcuate nucleus is consistently the most sensitive of these nuclei to MSG and aspartame toxicity. We know that this nucleus regulates growth hormone secretion, by way of the pituitary. But, what is less well appreciated is the fact that this nucleus has intimate connections to the other nuclei, such as the supraoptic nucleus and paraventricular nucleus. Indeed, when animals are given doses of MSG or aspartame, these nuclei are injured as well. Several studies have shown shrinkage of the pituitary, thyroid, adrenals and gonads in animals exposed to high concentrations of these excitotoxins. In addition, a consistent finding is gross obesity in animals exposed to these excitotoxins early in life. Some have raised the question concerning the connection between a high intake of food borne excitotoxins and the dramatic rise in childhood obesity over the past two decades. In animals made obese by damaging hypothalamic nuclei, one frequently sees accompanying violent outburst. We also know that directly injecting micromolar quantities of MSG into certain hypothalamic nuclei can precipitate an explosion of violence in experimental animals. The hypothalamus is one of the areas of the brain not protected by the blood- brain barrier. This is of special concern during childhood, since exposure to high intakes of excitotoxins, such as aspartame, can alter the development of the hypothalamus, leading to sexual maldevelopment and endocrine problems that will appear later in life. For example, we know that infant animals exposed to excitotoxins will have fewer offspring and the offspring will be smaller than normal. When the hypothalamus is exposed to excitotoxins early in life, the neural connections are often misdirected. Something I have called, mis-wiring of the brain. What this means is that a mis-wired hypothalamus will not react normally to the internal and external environmental cues that normally control our endocrine system. This could lead to infertility, hypothyroidism, adrenal hypoactivity, growth retardation and even emotional or intellectual problems later in life. All of these have been reported in studies using excitotoxin models. Many other problems have been traced to excitotoxin damage to the hypothalamus. For example, it is known that exposure of infants to high dose excitotoxins can result in immune system impairment throughout life. This would translate into more infections, cancer, and autoimmune diseases. Recently, Trocho and co-workers discovered that the methanol in aspartame appears to attach to the DNA of cells after it is metabolized to formaldehyde, and is not only very difficult to remove, but results in numerous DNA deletion injuries. This could increase cancer risk as well as risk of other degenerative diseases, such as lupus, diabetes and Alzheimer's disease. It is now known that glutamate ( and therefore aspartate) is the major neurotransmitter in the hypothalamus and therefore excess concentrations may affect all of the various nuclei in the hypothalamus. This means that virtually every function of the hypothalamus is vulnerable to excitotoxin damage, both subtle and acutely dramatic, depending on the dose. In normal everyday life we are exposed to numerous excitotoxins added to foods and drinks, in the form of MSG, cysteine and aspartame. Several studies have shown that these toxic doses are synergistic, that is, they are more than just the sum effect of each excitotoxin. Therefore, a meal of MSG laden soup, a diet cola and foods with hydrolyzed vegetable protein and natural flavoring, could easily damage the hypothalamus, as well as other portions of the nervous system. During pregnancy, the deleterious effects could be even more devastating, since it will affect the development of the brain itself. Another possibility, is the effect of excitotoxins on the sympathetic nervous system-controlling centers in the hypothalamus. Over stimulation could result in cardiac electrical abnormalities leading to sudden death. This has been demonstrated by hypothalalamic stimulation experiments. There have been clinical reports of cardiac related emergency room visits following a meal high in excitotoxin additives. Sudden deaths following such meals have also been reported. Since most hospitals rarely consider this in their differential diagnosis, we have no accurate data as to the number of ER visits and deaths related to this event. I suspect the numbers would be quite high. In conclusion, there is compelling evidence to indicate that food additive excitotoxins, such as aspartame, pose a serious danger to our well being, especially so in the case of children and the elderly. It has been demonstrated that excitotoxins in the diet can dramatically elevate free radical generation for prolonged periods of time and that once induced, it triggers a viscous cycle that ends in neuron death. Most authorities now agree that elevated free radical generation is associated with virtually all degenerative diseases as well as most injuries and toxins. It makes little sense to expose the general public to a product that we know increases free radical generation so dramatically and is associated with laboratory proven injuries to the nervous system. Russell L. Blaylock, M.D. Neurosurgeon 9 Lakeland Circle, Suite A Jackson, Ms 39216