THE OBESITY EPIDEMIC:
SHOULD WE BELIEVE WHAT WE READ AND HEAR
If you stand on a street corner used by many pedestrians or at the entrance of a high school at the beginning or end of the day, you will observe not only what would be considered to be obese people, but a number of people, including the young, who would be considered grotesquely obese.
If one is to believe the reports of the media,(2-3) often based on the findings of researchers,(4) obesity is mainly the result of poor nutrition and lack of adequate exercise. Psychological problems, poor parenting, and genetics are also reported as contributing factors.
Although what we read and hear through the media seems logical, one must ask whether the perceived reasons for obesity are, in fact, the actual causes, and whether researchers are looking in the right places for the causes of obesity and a possible resolution of the problem.
The purpose of this paper is to raise awareness of a more likely cause of the obesity epidemic than you have read and heard of, and to encourage researchers, including those at the Centers for Disease Control and Prevention (CDC) and the National Institutes of Health, to consider the points raised in this paper. Also, if the reader feels that the material in this paper makes sense, it is hoped that the reader will take time to write to his or her representatives in Washington to request that the Food and Drug Administration (FDA) be forced to be responsive to the facts they already know about obesity, and take appropriate action. (See conclusion of this article.)
A NEW PHENOMENON
What has changed through the years?
Simply stated, our food supply has changed along with the changes in our lives brought about by the demands of our fast-paced society. We are depending more and more on processed foods, and with each year, the FDA approves more and more chemicals for use in foods. With each year, the food industry is using more and more chemicals in their products. These chemicals increase shelf life, kill bacteria, improve taste, replace fats, replace carbohydrates, even replace meat in some vegetarian preparations, and more. Most important to food producers, chemical use can increase profits. Most important to the consumer is the fact that some of the chemicals are neurotoxic and/or carcinogenic.
For purposes of this paper, we will report on the neurotoxins MSG (glutamic acid that has been freed from protein through a manufacturing process - what many MSG-sensitive people refer to as processed free glutamic acid) and aspartic acid (about 40% of the sugar substitute aspartame).
In 1968, John W. Olney, M.D., a respected researcher at Washington University Medical School, St. Louis, Missouri, and member of the National Academy of Science, found that mice in his laboratory that were being used to replicate a 1957 study by Lucas and Newhouse, in which the administration of MSG had resulted in retinal damage,(5) had become grotesquely obese. Dr. Olney decided to sacrifice some of the mice and found lesions in the hypothalamus portion of the brain, the portion of the brain, as defined in Stedman's Online Medical Dictionary, that is "...prominently involved in the functions of the autonomic (visceral motor) nervous system and, through its vascular link with the anterior lobe of the hypophysis, in endocrine mechanisms; it also appears to play a role in neural mechanisms underlying moods and motivational states."(6)
Dr. Olney published a paper on his findings in 1969, in which he described the hypothalamic lesions, stunted skeletal development, and obesity in maturing mice which had been given the food ingredient "monosodium glutamate" as neonates. Olney also commented on observed pathological changes found in several brain regions associated with endocrine function in maturing mice.(7)
Neuroscientists have found in animal studies that glutamic acid and aspartic acid load on the same receptors in the brain, cause identical brain lesions and neuroendocrine disorders, and act in an additive fashion.(10)
Research indicating that MSG causes damage to the hypothalamus has been carried out mostly on small laboratory animals, primarily the mouse and the rat. In the 1960s, a few studies looked at the effects of MSG on primates, using rhesus monkeys. The findings were the same for rhesus monkeys as they were for rodents.(11-12) Although research designed to produce brain lesions cannot be carried out on humans, neuroscientists have determined that humans are 5 times more sensitive to MSG than the mouse and 20 times more sensitive to MSG than the monkey, based on blood plasma levels of glutamate following an oral dose of 150 mg/kg of glutamic acid.(13) Furthermore, individual variability in plasma response to glutamate loading is more extreme in humans than in the mouse or monkey.(14)
Neuroscientists have known that MSG and aspartic acid cause lesions in the hypothalamus since 1969, but only recently has a possible explanation for the mechanism by which this occurs come to light. In 1994, researchers discovered the appetite-suppressing hormone, leptin. As described in many articles, leptin regulates, among other things, energy, control of appetite, and body weight. Leptin acts by altering neuropeptide circuits in the hypothalamus.(15-20)
While there is abundant literature demonstrating that MSG and aspartic acid cause hypothalmic lesions which, in turn, can cause gross obesity, I know of no research that has examined a possible relationship between the hypothalamic damage caused by MSG and/or aspartame, and the leptin abnormalities found in obese individuals. Research is needed in this area.
In July, 1992, the Federation of American Societies for Experimental Biology (FASEB) issued its findings on an FDA-funded study entitled "Safety of Amino Acids Used as Dietary Supplements." In the section on glutamic acid (the reactive component of the food ingredient "monosodium glutamate"), the report concluded, in part, that "The continuing controversy over the potential effects of glutamate on growth and development of neonatal animal models suggests that it is prudent to avoid the use of dietary supplements of L-glutamic acid by pregnant women, infants and children. The existence of evidence of potential endocrine responses, i.e. elevated cortisol and prolactin, ... would also suggest a neuroendocrine link and that supplemental L-glutamic acid should be avoided by women of child bearing age and individuals with affective disorders."
The FDA appears to have suppressed this FASEB finding. When asked how the FDA can allow MSG to be used in food, FDA officials stated that one cannot compare the free glutamic acid in supplements to the free glutamic acid in food. Of course, this position is completely untenable since food products contain far more free glutamic acid than supplements. Following issuance of the FASEB report on supplements, the FDA contracted with FASEB for over $500,000 to conduct a study on the safety of MSG in food. In July, 1995, FASEB published its report entitled "Analysis of Adverse Reactions to Monosodium Glutamate (MSG)." Most people who inquired, and the media, received a 20 page "Executive Summary," primarily made up of questions developed by the FDA and the answers to those questions. The carefully crafted summary left readers with the impression that MSG was essentially safe.
What is not generally known about the FASEB report on the safety of MSG in food is that the original draft final report was issued to the FDA in September, 1994, and leaked to the glutamate industry. The glutamate industry was not happy with FASEB's report and the FDA rejected it. The FDA paid FASEB over $100,000 in additional money to "clarify" the report, leading to the final report, dated July, 1995. A reading of the entire July, 1995, FASEB report (over 350 pages long rather than the 20 pages making up the Executive Summary), will not give the reader the impression that MSG is safe.
Since there is no question that MSG and aspartame cause lesions in the hypothalamus, the portion of the brain that is recognized to affect weight, I call upon scientists to consider the destructive qualities of glutamic acid and aspartic acid as they expand their search into the reasons for obesity. In particular, I urge those who are exploring the role of leptin in obesity to consider that it may be the relationship of leptin to a hypothalamus damaged by MSG and aspartame that results in the inability of some people to control food intake, and resulting obesity.
What can be done to stem the obesity epidemic? I would start by identifying the sources of MSG in processed food. MSG should be fully disclosed on processed food labels. I ask that all processed food be measured for "free glutamic acid," post production, and when free glutamic acid is found to be present, it be disclosed on the product label as "MSG," with the amount present stated in milligrams. Such an action would stop the accelerating use of MSG, and likely cause its current use to drop because some people would recognize their intolerance for MSG. Others, realizing its toxicity, will choose to avoid it.
Aspartame should be withdrawn from the market. There is no need for aspartame or the recently approved sweetener, neotame, described by some as a super aspartame.
Your thoughts on this matter should be submitted to your representatives in Washington, to the FDA, and to the CDC. Your submission might include the suggestion that all MSG should be disclosed on processed food labels and that all aspartame products be withdrawn from the market.
Please note. Since
publication of this article, we have been told by scientists that
repeated ingestion of MSG increases levels of the hormone glucagon found
in the body. Elevated levels of glucagon then increase insulin levels,
leading to a feeling of hunger and, therefore, overeating.
1. A book by Russell L. Blaylock, M.D., a neurosurgeon, entitledExcitotxins: the Taste that Kills. Health Press, 1995
2. A published paper by John W. Olney, M.D. It is entitled Excitatory Neurotoxins as Food Additives: An Evaluation of Risk. The paper was published in Neurotoxicity in 1980. It will be found in volume 2 on pages 163 to 192
3. Web site of the Truth in Labeling Campaign regarding MSG (www.truthinlabeling.org/index.html)
4. Web site regarding aspartame (www.dorway.com)
Jack Samuels and his wife Adrienne Samuels, Ph.D., are founders of the Truth in Labeling Campaign, a nonprofit organization dedicated to accurate labeling of MSG and the removal of MSG from agriculture. For further information, see their website at www.truthinlabeling.org.