Things You Should Know about MSG

There are several things that MSG becomes one of the famous ingredients that made people debate. The debate about the safety, individual sensitivity and sources. It enhances the taste of food, but some people still avoid putting it in their food because assume it engages in several symptoms such as headache, asthma, and nausea. These symptoms appear after a meal of Chinese food and we call it with Chinese Restaurant Syndrome (CRS). But, the question, is it terrible for health? In contrast, the Food and Drug Administration (FDA) has classified MSG as “generally recognized as safe” (GRAS). So, it means MSG is safe, yet not for people who sensitivity to it. This article tries to explore the statements it is safe or vice versa.

What is Monosodium Glutamate?

MSG which stands for monosodium glutamate, a sodium salt of glutamic acid, which is a non-essential amino acid. Glutamate is naturally present in our bodies and found in many foods that rich in protein. It is used to enhance the taste of food, possess a unique taste, called “umami” which translate as “savoury”. Umami is the fifth taste along with sweet, sour, salty and bitter. And it also can decrease the need for salt because the ingredient has two-thirds less sodium than table salt.

How is Monosodium Glutamate made?

1866 was the first-time amino acid glutamate isolated by Rithausen from protein in wheat. Later, 1908, Kikunae Ikeda, a professor at the Imperial Tokyo University, extracted glutamate from seaweeds and found umami taste. After that, they found MSG more stable and in the 1950s via fermentation processes produced it from sugar beet molasses and carbohydrate sources. It is resistant to humidity, and very stable in various storage conditions.

Glutamate in Monosodium Glutamate

Glutamate is the magic ingredient in monosodium glutamate. It is amino acid in all protein foods that contributes about 8-10% of amino acid content in the average dietary proteins such as tomatoes, almonds, soy sauce, spirulina, soy protein isolate, parmesan cheese, beef loin, whey protein isolate and bacon. Hence, among various forms of glutamate, the sodium form (MSG) has the most flour enhancer and umami potency.

How does Human Body treat Glutamate and MSG?

The body treats glutamate in the same way, either from food or adding glutamate in MSG as seasoning. In addition, glutamate is non-essential amino acid, it means our body can produce it. Besides, heating during cooking process extracts it, it also releases from the protein chain in the small intestine because of the action of digestive enzymes. Contain in the human amniotic fluid and breast milk, also in the human brain.

Human Body and Monosodium Glutamate

In the human gastrointestinal tract, less than 5% of the ingested glutamate passes from the gut into the circulation and none transits the placenta or the blood-brain barrier (BBB).  Glutamate has important nutritional benefits, namely energy for the cells of the digestive system. The process starts when intestinal lumen absorbs glutamate, intestinal cell immediately metabolizes it to generate ATP- energy necessary for intestinal motility. The normal dietary consumption of MSG as seasoning has no effect on plasma glutamate concentration because of the rapid metabolism and use of glutamate in the intestine. Furthermore, intake high level of MSG than normal dietary consumption, for instance, 12 g will elevate plasma level however it will normalize within 2 hours after that consumption.

Looking more closely at human infant, human amniotic fluid and breast milk contain glutamate it has shown even infants to possess the capacity to effectively metabolize glutamate as the adult. Placenta forms a natural barrier to the penetration of glutamate from maternal into fetal circulation, and glutamate in breast milk also does not rise. More to the point, normal dietary consumption of MSG and levels of glutamic acid in food do not raise toxicological concern in infants. In human brain, glutamate has roles in learning and memory formation. The brain content glutamate is much greater than plasma concentration. The blood-brain barrier (BBB) has an active transport system that expels glutamate from the extracellular fluid. The brain produces glutamate itself from tricarboxylic acid cycle, not from food or MSG. Glutamate does not produce any effect on the human brain, even plasma glutamate is increased tenfold.

Monosodium Glutamate Intake

Data in USA and Europe showed an average daily consumption of food-added MSG at about 0.6 g with a range of 0.3-1.0 g/day. In East and Southeast Asia diets, MSG intake is 2-3 times higher when compared to Europe. Taiwan range 1.5-3.0 g/day, Japan range 1.1–1.6 g/day, South Korea range 1.6–2.3 g/day and 4-6 g/day in Indonesia. In addition, MSG dietary consumption represents but a small fraction (5-10%) of the total daily glutamate intake from various dietary sources.

Monosodium Glutamate Safety

Monosodium glutamate is safe, even though it has been controversial to cause symptoms such as headache, flushing, nausea, and asthma. Many studies published the effects of MSG on obesity, cancer, poisoning, children, pregnant and lactating women, neurological effects. The result was there is no evidence of a link between MSG and these symptoms or someone specific condition. Even for the children as young as a one-year-old, metabolize glutamate as effectively as adults. FDA has classified MSG as “generally recognized as safe” (GRAS) and never able to confirm that it caused symptoms. Nevertheless, people sensitive with that report some symptoms like CRS and short-term reactions who consume 3 g or more without food.

In conclusion, MSG is safe, consuming it does not present any of the disease conditions. it even has roles in physiological functions such as energy for the cells of the digestive system. Furthermore, it suggests to sensitive individuals to avoid foods containing MSG.

References

1. Food and Drug Administration n.d., Questions and Answers on Monosodium Glutamate (MSG), Food and Drug Administration, accessed 13 May 2020, <https://www.fda.gov/food/food-additives-petitions/questions-and-answers-monosodium-glutamate-msg>.
2. Henry-Unaeze, 2017, Update on Food Safety of Monosodium L-glutamate (MSG), Pathophysiology, 24 (4): 243-249.
3. Amidor, Toby, 2018, Scientist Have Known MSG is Safe for Decades. Why Don’t Most Americans?, Health US. News, accessed 13 May 2020, < https://health.usnews.com/health-news/blogs/eat-run/articles/2018-10-10/scientists-have-known-msg-is-safe-for-decades-why-dont-most-americans>.
4. Leech, Joe, 2018, Monosodium Glutamate (MSG): Good or Bad?, Healthline, accessed 13 May 2020, <https://www.healthline.com/nutrition/msg-good-or-bad>.
5. Hull, Michael, 2019, Is MSG (Monosodium Glutamate) Bad for Your Health?, Examine.com, accessed 13 May 2020, < https://examine.com/nutrition/is-msg-bad-for-your-health/>
6. International Glutamate Information Service n.d., The Scientific Research Supporting the Safety and Benefits of Monosodium Glutamate (MSG) is Extensive, International Glutamate Information Service, accessed 13 May 2020 < https://glutamate.org/safety/msg-safety-fact-sheet/>.
7. Direktorat Jenderal Pelayanan Kesehatan Kementrian Kesehatan Republik Indonesia, 2018, Berbahayakah MSG bagi Tubuh?, Kementrian Kesehatan Republik Indonesia, accessed 13 May 2020 < http://yankes.kemkes.go.id/read-berbahayakah-mgs-bagi-tubuh-5679.html>.
8. Bera, T.K., Kar, S.K., Yadav, P.K., Mukherjee, P., Yadav, S., Bishal, J., 2017, Effects of Monosodium Glutamate on Human Health: A Systematic Review, World Journal of Pharmaceutical Sciences, 5 (5) : 139 – 144.