Monosodium Glutamate

Monosodium glutamate (MSG), also known as sodium glutamate, is the sodium salt of glutamic acid, one of the most abundant naturally occurring non-essential amino acids. Glutamic acid is found naturally in tomatoes, grapes, cheese, mushrooms and other foods. MSG is used in the food industry as a flavor enhancer with an umami taste that intensifies the meaty, savory flavor of food, as naturally occurring glutamate does in foods such as stews and meat soups.

The U.S. Food and Drug Administration has given MSG its generally recognized as safe (GRAS) designation. Some sources indicate that MSG is known to cause headaches and other feelings of discomfort, known as "Chinese restaurant syndrome," but the majority of studies fail to find evidence of such a reaction. However, some neurologists maintain that MSG may be a migraine trigger. Therefore, the European Union classifies it as a food additive permitted in certain foods and subject to quantitative limits.

MSG has been used for more than 100 years to season food, with a number of studies conducted on its safety. Consumption and manufacture of high-salt and high-glutamate foods, which contain both sodium and glutamate, stretch back far longer, with evidence of cheese manufacture as early as 5,500 BC. Under normal conditions, humans can metabolize relatively large quantities of glutamate, which is naturally produced in the gut in the course of protein hydrolysis.

The claim is that MSG leads to excessive glutamate in the brain and excessive stimulation of nerve cells. Glutamic acid functions as a neurotransmitter in your brain and it stimulates nerve cells in order to relay its signal. It is a fact that increased glutamate activity in your brain can cause harm and large doses of MSG can raise blood levels of glutamate. However, dietary glutamate should have little to no effect on your brain, as it cannot cross the blood-brain barrier in large amounts. It does cross to some degree.

You will find many information sources that state empirically MSG is not harmful to human beings. Never trust these sources as there is some evidence that a possibility exists MSG can be harmful to some people. There are also no studies on accumulative impact of MSG of a period of many years. Even Wikipedia fails to provide accurate information on the topic. It can only be said truthfully that MSG consumption of normal amounts found in food under normal conditions for most people is not immediately harmful. Any statement beyond that is opinion and not fact since there is no research to provide otherwise.

You can mitigate the consumption of MSG, however, if you live in the United States you probably cannot avoid some degree of consumption. Some restaurants that claim to have MSG free food have been found to be using MSG or in many circumstances their food supplier had used MSG in the processing and therefore the food already had MSG prior to delivery to the restaurant. Either way, you may ingest MSG without knowing it, and otherwise while you attempt to avoid it, you will likely suffer no negative impact with the occasional accidental consumption of MSG.

Some people may experience adverse effects from consuming MSG due to a condition known as Chinese restaurant syndrome or MSG symptom complex. Symptoms included headache, muscle tightness, numbness, tingling, weakness and flushing and is somewhat supported by a 1997 study in which people with self-reported MSG sensitivity consumed either 5 grams of MSG or a placebo and 36.1% reported reactions with MSG compared to 24.6% with a placebo.

• The monosodium glutamate symptom complex: Assessment in a double-blind, placebo-controlled, randomized study - June 1997

The threshold dose that causes symptoms seems to be around 3 grams per meal which is far greater than what you would ordinarily find in any meal at a Chinese restaurant or grocery store purchased snack food, we hope. The FDA should force companies to indicate how much MSG is in a food product. For example, Nabisco Chicken in a Biskit Baked Snack Crackers contains Monosodium Glutamate, however, the box does not indicate how much, and neither does the Nabisco web site.

Possible side effects of consuming excessive amounts of MSG:

• headache, muscle tightness, numbness, tingling, weakness and flushing
• asthma attacks in susceptible individuals
• weight gain

Although many believe MSG might tend to make a person feel more full after consuming a meal, some studies indicate the opposite. In China, increased MSG intake has been linked to weight gain with average intake ranging from 0.33–2.2 grams per day.

It has been suggested by researchers that Pregnant women should avoid the consumption of MSG.

Again, under normal conditions with limited consumption of MSG you should suffer no ill effects. Long term impact over years of consumption is completely unknown. If you feel as though MSG is causing a health concern then proactively limit your consumption as much as possible. Alcohol consumption will do more harm to your body and brain by drinking a glass of Vodka when compared to eating Chinese takeout pointing to the overwhelming evidence of complications due to alcohol in countless research studies. If you are going to avoid putting bad things into your body then MSG might be one to avoid, but should be nowhere near the top of the list.