Monosodium glutamate (MSG) is the salt of sodium and glutamate, a naturally occurring amino acid that is present in all proteins such as milk, meat, fish and many vegetables. In chemistry, mono- means one, thus monosodium refers to one molecule of sodium. MSG has been used for more than 100 years to enhance and balance the taste of many dishes. It adds umami taste, which is best described as savory, broth-like or meaty taste.
Glutamate is produced by fermentation of starch, sugar beets, sugar cane, or molasses. The fermentation process is similar to that used in making wine, vinegar, soy sauce and yogurt. The glutamate is purified and crystallized before drying, resulting in a finished product that dissolves easily and blends well in foods.
The glutamate in MSG is chemically indistinguishable from the glutamate in foods or the glutamate in our body, they are all identical.
Does the human body process the glutamate occurring naturally in foods differently from the glutamate added to foods in the form of monosodium glutamate?
No. The body cannot distinguish the naturally occurring glutamate in food such as tomatoes or cheese from the glutamate in MSG. Once they are ingested, our body makes no distinction. In fact, research has shown that glutamate from food or from MSG is important for the normal functioning of the digestive system.
- After more than 40 years of extensive studies, international and national bodies dedicated to the safety of food additives have determined that MSG is safe for consumption as a flavor enhancer.
- The U.S. Food and Drug administration considers the addition of MSG to foods “generally recognized as safe” (GRAS), similar to other ingredients like sugar, baking powder and vinegar. Foods are designated GRAS according to their common use and extensive testing. In the European Union, MSG is a food additive that has been confirmed by scientific and regulatory bodies to be safe for human consumption.
- Although some people identify themselves as sensitive to MSG, scientists have not been able to consistently trigger reactions in double-blind studies with such individuals using MSG or placebo when combined with food.
MSG is safe for everyone without exception, including infants and pregnant women. Studies with infants showed they metabolize MSG in just the same way as adults. In fact, human breast milk contains 6 to 9 times higher glutamate than cow’s milk. Infants can taste glutamate right after they are born. It is a taste they naturally prefer. More information about MSG’s safety for use by children and pregnant women is available here.
In 1968, accounts of reactions to food from Chinese restaurants in the USA were reported. MSG was mistakenly blamed by some people as the cause for these symptoms, such as headaches or flushing, and the people who believed they had this reaction were considered sensitive to MSG. However, studies conducted by recognized medical research institutions fail to show a conclusive connection between MSG consumption and adverse health effects. Learn more facts about alleged MSG side effects here.
- According to the U.S. National Institute of Allergy and Infectious Diseases, the reaction that some people claim to have to certain additives such as MSG can be confused with food allergy when in fact it should be considered food intolerance. Some individuals claim to be sensitive to MSG, but there are no known mechanisms that would explain the reason why MSG would cause any intolerance.
- In comparison, food allergy is an adverse response from the body’s immune system to a particular food that in rare cases can trigger a severe and life threatening reaction known as anaphylactic shock. Foods that most often generate allergic reactions are fish, shellfish, peanuts and nuts.
Although headache was reported as one of the symptoms of the so-called “Chinese Restaurant Syndrome,” human studies have not been able to prove it consistently. Headache appeared as a symptom in some studies only when MSG was consumed without food during fasting, which is irrelevant because MSG is a flavor enhancer and would not be ingested without food.
In fact, in January 2018 the International Headache Society removed MSG from its list of causative factors for headaches. Previously, MSG had been listed as a substance attributed to headaches in the Society’s International Classification of Headache Disorders (ICHD). Now, in the ICHD 3rd edition, based on the latest scientific evidence MSG has been removed from this list.
The U.S. Food and Drug Administration (FDA) received reports of headaches and nausea from people that ate food containing MSG. To clarify whether MSG caused these effects, in the 1990s the FDA asked an independent scientific group, the Federation of American Societies for Experimental Biology (FASEB), to examine the safety of MSG. FASEB concluded that MSG is safe, but that some sensitive individuals may present some short-term, transient and generally mild symptoms (headaches, numbness, flushing, tingling, palpitations and drowsiness) after consuming 3 grams of MSG, although consuming 3 grams of MSG at once without food is a very unlikely event.
The taste of MSG, like the taste of salt, is pleasant only within a relatively narrow concentration range. A small amount of MSG is sufficient to achieve optimum flavor. Further addition of MSG has little or no beneficial effect. In fact, too much MSG can reduce the appeal of a dish.
Many countries require that packaging labels include MSG in the ingredient panel when they contain added MSG. However, foods may also include other food ingredients that inherently contain MSG, such as hydrolyzed vegetable proteins or yeast extracts. Other foods like cheeses or tomatoes are also naturally rich in MSG (glutamate).
Does the addition of MSG allow food manufacturers to substitute poor quality ingredients for high quality ingredients?
MSG adds umami taste and enhances the original flavor of foods, but MSG cannot improve the quality of inferior ingredients.
MSG can be used in many savory dishes such as meat, fish, poultry, or vegetables, as well as in sauces, soups, and marinades. Read more about foods with MSG occurring naturally, foods that are rich in the umami taste.
Is the amount of glutamate added to foods for flavor greater than the amount of glutamate found naturally in foods?
The glutamate added to foods for flavor represents only a small fraction of the total amount of glutamate consumed in the average daily diet. Normally, a person consumes between 10 and 20 grams of glutamate every day. The average added intake of glutamate from MSG amounts to just 0.5 – 1.5 grams per day.
The amount of sodium from MSG is minor compared to table salt and other food sources in the diet. Overall, only about 1 to 2% of total sodium contained in the average diet comes from MSG. Table salt has roughly 3 times more sodium than MSG and it is used more readily. MSG is used in lesser quantities; it tastes stronger than table salt.
MSG is gluten-free.