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On 11/03/97 Joe Bruman asked: >Can anyone answer this question? What's the relation, if any, >between the family of natural glutamates (neurotransmitters >such as NMDA, arising in the striatum and subthalamic nucleus >and considered neurotoxic when present in excess) and the popular >"Chinese restaurant" condiment monosodium glutamate (MSG)? Joe: MSG or momosodium glutamate is the sodium salt of glutamic acid. It is a naturally occurring flavor enhancer found in a number of plants and in milk. It is produced commercially from sugar beets and other plant products that are good sources of glutamic acid. Casein, a milk protein, is also an important source. Among the foods that provide significant amounts of natural MSG are Parmesan and Roquefort cheeses, mushrooms, walnuts, broccoli, and tomatoes. (Hmmm...the tomatoes, mushrooms and Parmesan along with gluten rich pasta sounds a lot like the foods we were discussing recently.) The western diet includes about 0.3 grams of free glutamate per day, while in southeast Asia, the amount is 3 grams. Soy sauce is a major contributer there. Some people are sensitive to MSG and experience a variety of neurological symptoms. It is not an allergy, but a sensitivity that may be related to a metabolic defect. Adequate dietary vitamin B6 has been found to help alleviate symptoms in some susceptible subjects. Sensitive people should avoid excessive intake of natural food sources and take care in avoiding additive sources. This is not worrisome for most of us for, as the Institute of Food Technologists (IFT) reported, it would take 50 tablespoons of Parmesan cheese at a sitting to get a large enough dose of natural MSG to cause an unpleasant neurological reaction from sensitive people who do not have asthma. Since an estimated 25 to 30% of the U.S. population may be sensitive in some degree to commercially added MSG, there have been ongoing arguments concerning the FDA approval of MSG as a GRAS (Generally Recognized as Safe) food additive. When added to foods, it is labelled as monosodium glutamate. The Institute of Food Technologists have issued Information papers on this subject. One of these is found at http://www.oznet.ksu.edu/dp_fnut/_timely/MONO.HTM Another informative source is that of The Glutamate Association at http://www.msgfacts.com A very informative source is in the Medical Sciences Bulletin section at http://www.pharminfo.com Glutamic acid (alpha-amino- glutaric acid) is an amino acids which performs the transamination and deamination processes that allow nutrients to be assembled into body chemicals that are essential for life. It is also an ingredient of folic acid. When glutamic acid combines with ammonia in brain, liver and kidneys, glutamine is formed. This compound can cross the blood- brain barrier where it supplies the glutamic acid needed to participate in cell oxidation, the process of getting energy from nutrients. Glutamate, is one of the excitatory amino acids, which function as nerve transmitters in the central nervous system. Aspartic Acid is the other. We have had a discussion in the past here on the list about the incompatability of foods and beverages sweetened by aspartame for people with PD. Do we also have a problem with Glutamate? Martha Rohrer CG for Neal, 77/12 [log in to unmask]