Monosodium glutamate, or MSG, is a popular ingredient used by Asian restaurants to enhance savory flavors. Popularly known as Ajinomoto, it is widely believed to be a harmful compound. But is it?
What is MSG?
MSG is the sodium salt of the abundantly occurring glutamic acid. Glutamic acid is a non-essential amino acid that gives meaty flavor to stews and broths. MSG is a flavor enhancer for savory foods, and is used widely in Chinese restaurants.

MSG was identified by German chemist Karl Heinrich Ritthausen in 1866 when he wheat gluten with sulphuric acid. In 1908, Japanese chemist Kikunae Ikeda identified MSG as flavor component. He obtained it from kombu seaweed via aqueous extraction and subsequent crystallization.

Ikeda called its taste “umami”. Ikeda called his product “monosodium glutamate”, and submitted a patent to produce MSG. In 1909, he found a way to commercially manufacture MSG from wheat and soya beans. The product was copyrighted as Aji-no-moto (essence of taste), and MSG is commonly called by that name all over the world.

Where is MSG found?
MSG is a salt of the glutamic acid, which occurs naturally in abundance in most proteins. Even human bodies contain these proteins. Some items, like tomatoes and cheese, have high amounts of MSG.

MSG side effects
MSG has been used in Asian restaurants for decades. Food and Drug Administration (FDA) classifies MSG as a food ingredient that’s “generally recognized as safe”.

MSG is rumored to be unsafe, and consuming large amounts of it is said to cause headaches. These headaches were once called the “Chinese restaurant syndrome.” However, there is no evidence to support this claim.

MSG Chinese Food Myth
Some early studies tried to link MSG with headaches and breathing troubles. Some anecdotes were prevalent that people developed these symptoms after eating at Chinese restaurants, where MSG is widely used. No evidence was found to back the existence of this “Chinese restaurant syndrome.”

Some have attributed these rumours to anti-Asian sentiments. Critics have pointed out that this comes from a Western-centric mindset, which does not take into account the wide-spread use of MSG in Asian or Chinese cuisine.

Another prevalent myth is that MSG is linked to obesity. Tests conducted in this area have been inconclusive.

Is MSG bad for your health?
Humans have been consuming foods rich in sodium and glutamate for thousands of years. No evidence exists to show it is harmful. Still, why do people regard it as harmful?

Glutamate is a neurotransmitter for brains. It is an “excitatory” neurotransmitter, that “excites” the neurons while conveying stimuli.

Experiments on mice showed that when injected with high amounts of glutamate, they showed symptoms or brain damage and also lead to death in some. In females, it increased sterility and in some adult mice, there were signs of stunted growth.
The results of this study might be the basis of fears about MSG. However, there is no evidence that shows that such drastic change in glutamate can happen from eating foods containing MSG. Several experiments showed eating food with MSG had no effect on humans.

MSG Production Process
For large-scale commercial uses, MSG is obtained from natural materials like corn starch, sugar cane, molasses and sugar beets. The fermentation process used to make MSG introduces micro-organisms to syrups, letting the former to produce proteins that are necessary for themselves.

Many enzymes are used subsequently, which makes these micro-organisms produce a number of amino acids. This method has been popular since the 1960s. Earlier, the extraction method was used for commercial production.