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Foodies can’t stop talking about umami — the savory taste that’s taking over the culinary scene and which, along with sweet, sour, bitter, and salty, is one of the five basic tastes that our tongues perceive. But if you’re a fan of Chinese takeout, you’ve been team umami from the get-go.

That’s because MSG— that flavoring often associated with American Chinese food— is umami in its purest form. And while you might have been told it’s bad for you or causes the so-called “Chinese Restaurant Syndrome,” science disagrees. As much as we associate MSG with Chinese food, there isn’t anything inherently Chinese, or even Asian, about the compound.

MSG stands for monosodium glutamate—the sodium salt of glutamate— an amino acid that the human body can synthesize, but that we also get from our food. Like other amino acids, glutamate is an important building block for proteins, and it also helps nerve cells send signals to other cells in the body— it’s the most abundant excitatory neurotransmitter in vertebrates. Since it’s so important for our bodies, it’s not surprising we’ve evolved a taste for it.

We have umami-specific receptors on our tongues and in our stomachs, and these drive our love for foods that contain glutamate like tomatoes, mushrooms, and aged cheeses. And umami-rich foods have been staples in human diets for, well, /forever/. For example, historians call the concoction known as Garum— an umami-filled sauce made from fermented fish guts—the ketchup of ancient Rome.

And we’ve been concentrating available, naturally-occurring glutamate by sun-drying tomatoes and curing meats for centuries, long before we knew what amino acids were. Even babies seem to like MSG, which makes sense, because human milk is naturally rich in glutamate. But purified MSG wasn’t a thing until 1908, when a Japanese chemist realized that the base made from kombu seaweed in his soup imparted a delicious flavor that wasn’t one of the four previously-established tastes.

He soon isolated the crystalline salt of glutamate from the kelp, striking culinary gold. He called the crystals Ajinomoto, which means essence of taste. And it wasn’t long before MSG became commercialized.

In Asia, it was branded a staple for any modern cook, and quickly became ubiquitous in kitchens across Japan and China. By the early 1930s it had gone global, with companies like Heinz and Campbell’s adding MSG to their products. And even the US military hopped on the MSG train.

During World War II, the army used the best available food science to develop nutritionally dense rations with long shelf lives, called K-rations, but soldiers hated them because they were super bland. So, in the late 1940s, they started adding MSG to them, and suddenly, they weren’t so reviled. Our universal love for MSG isn’t just from its savory goodness.

Studies have shown that umami functions as a flavor enhancer, creating a harmony between various flavors and aromas and adding a sort of dimension to both— a phenomenon known as umami synergy. That sounds kind of nebulous, but consider a 2007 study published in the European Journal of Neuroscience. Researchers as Oxford University had twelve volunteers sip an umami drink made of water, MSG, and the nucleotide ii while sniffing a vegetable aroma.

On their own, both the umami drink and the vegetable aroma were considered unpleasant and bland. But when combined, they were rated higher, and they just seemed to go together better than a salty drink paired with the same smell. What was really telling, though, was that brain activity maps showed way more neurons associated with flavor and pleasure lit up from the combo than would have been estimated by adding up the isolated effects of each.

Given all this, you might be wondering why companies now proudly proclaim their food doesn’t contain MSG, or people say it makes them sick. Well, while our love of MSG comes from biology, a lot of people’s aversion to it seems to have roots in something else entirely—racism. It all started with a 1968 letter to the editor of the New England Journal of Medicine describing the author’s and his friends’ so-called Chinese Restaurant Syndrome following the consumption of Chinese food, including symptoms like heart palpitations, generalized weakness, and radiating numbness.

The idea took hold, spurring years of biased science based on the flawed assumption that Chinese Restaurant Syndrome was a real thing, and that MSG caused it. Subsequent animal studies seemingly confirmed the idea, but these often consisted of injecting super concentrated doses of MSG directly into creatures’ abdomens, which is not exactly a scientific approach to determining the effects of MSG sprinkled into saucepans. More recent research on MSG aversion has taken into account the xenophobia and racism that fueled it.

And over the last 3 decades, a number of double-blinded, placebo-controlled studies, including studies of subjects with reported sensitivity to MSG, have failed to find a reproducible response to ingesting foods with MSG. A much more likely explanation for feeling crummy after Chinese takeout is the nocebo effect, where you feel sick simply because of the belief that something will make you ill. Fortunately, scientists are one step ahead of the haters.

Investigation into potential health benefits of MSG is ongoing, with research suggesting it can help increase salivation and appetite in the elderly, increase satiety and therefore reduce caloric intake in those trying to lose weight, and help impart flavor while reducing overall dietary sodium. So yeah, MSG doesn’t deserve its toxic reputation. But you don’t need to avoid your favorite restaurant just because they use a little.

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