Glutamate no risk to health?

Chinese Restaurant Syndrome: facts or fiction

10.11.2011

The health effects of glutamate are still controversial. While some claim that the so-called flavor enhancers pose no health risk, individuals with glutamate intolerance complain of significant impairments after glutamate consumption.

In a recent study, Asian scientists have not been able to detect any negative effects of glutamate „Chinese restaurant syndrome“ into the realm of legends. Glutamate did not cause any health problems among the study participants, according to the statement of the current Asian study. For those affected by glutamate intolerance, a barely comprehensible statement, they are convinced that the taste enhancers regularly lead to symptoms such as headache, redness, muscle aches, palpitations, nausea and vomiting.

Chinarestaurant syndrome first described in 1968
The first scientific study on the potentially harmful effects of glutamate was published in 1968 by Dr. med. Robert Ho Man Kwok in the trade magazine „New England Journal of Medicine“ presented. The doctor reported to visitors to Chinese restaurants, who had a crimson face after eating and suffered from neck sweats, headaches and nausea until vomiting. Dr. According to Robert Ho Man Kwok, it seemed clear that glutamate's negative health effects were caused by eating. However, the following studies have not been able to establish a clear relationship between the so-called „Chinese restaurant syndrome“ and the glutamate content of the food. Thus, even the current studies of Asian researchers have no evidence of possible health threats caused by glutamate. Glutamates are the esters and salts of glutamic acid, which are naturally found in many foods. For example, all protein-containing foods contain glutamate. Especially natural glutamate is present in cheese and meat, but also fish, wheat or corn wholemeal flour, rice, peas and tomatoes contain glutamate. Even in breast milk, according to the scientists, glutamate is included. In the food industry, glutamate is mainly used in the form of monosodium glutamate as a flavor enhancer, often to give a little flavor to otherwise quite bland tasting ready meals. The glutamates used are metabolized in the human body in the same way as the naturally occurring glutamic acids.

Glutamate naturally contained in numerous foods
Also the German society for nutrition (DGE) explained in a current contribution opposite „World Online“, that „Glutamate naturally found in almost all foods“ be and we „about eight to twelve grams of glutamate per day in normal mixed diet“ take up. Glutamate not only enhances the intrinsic taste of foods and stimulates salivation, but is also required for basic functions of the human organism. Thus, glutamate is the most important excitatory neurotransmitter (messenger substances) in the central nervous system. The supposedly pathogenic glutamate is crucial for the transmission and processing of information in the brain, especially in the flow of information about the olfactory and taste nerves to the amygdala. According to the experts, glutamate also performs important tasks in cell division, for example in the area of ​​the intestinal mucosa. While, according to some scientists, the central importance of glutamate as a messenger substance suggests that the symptoms of the „Chinese restaurant syndrome“ Others might consider the natural presence of glutamate in the human organism as an argument against the negative health effects of flavor enhancers.

Food intolerance instead of glutamate intolerance cause of discomfort
As part of a comprehensive study, Asian scientists have therefore re-examined what health consequences glutamate can bring. The researchers were unable to establish a connection between the glutamate intake and health impairments. Although some study participants actually suffered from physical complaints after consuming the Asian dishes, these were not due to glutamate but to the incompatibility of other ingredients such as shrimp, peanuts, fish and soy sauce or special herbs. The health complaints had also occurred primarily in European and American study participants, indicating that they are not accustomed to the typical Chinese food and its ingredients therefore tolerate less well. According to the Asian researchers, this is „Chinese restaurant syndrome“ therefore rather due to general food intolerances, as to the high proportion of glutamate. However, when it comes to susceptibility to fish and soy sauce, it should be noted that these ingredients, which are commonly used in Asian dishes, contain a significantly higher level of glutamate. Fish sauce is traditionally made from anchovies and other small fish, with amino acids, peptides, flavors and natural glutamate that give the sauce its flavor during the approximately 18-month fermentation. Often the sauces are used in Asian cuisine instead of salt to spice up the dishes. For the taste of glutamate contained there is even a separate word in Japan: „umami“ - where besides sweet, sour, salty and bitter this indicates one of the basic tastes.

Whether glutamate is generally without health risks for the human organism or whether possibly some people still have a so-called glutamate intolerance, can not conclusively clarify the current study. However, the Asian researchers assume that the health complaints are usually caused by other ingredients of the food and not caused by the flavor enhancers. (Fp)