If you’ve seen the abbreviation MSG lately, there’s a good chance it was on the menu of a Chinese restaurant assuring customers that they don’t use the stuff. So it might surprise you to know that MSG or monosodium glutamate began its life as a tool to encourage healthy eating.

In a 2005 paper for Gastronomica, Jordan Sand traces the history of the controversial additive.

Sand begins his story in 1908, when Japanese chemist Ikeda Kikunae went looking for a way to make healthy, bland food more palatable. He isolated an ingredient in sea kelp that helped give konbu dashi, the ubiquitous Japanese broth, its flavor. Ikeda also came up with the word umami—“tasty” in Japanese—to describe MSG.

Ikeda’s invention came at a perfect time. Japan was pushing to compete with the West in technological innovations. The country’s educated middle class was excited about the new applications of modern science, including in the kitchen.

The Suzuki Chemical Company aimed its product squarely at this market, promoting its Ajinomoto brand MSG as a predictable, convenient, scientifically proven product. By 1939, its use in home kitchens was so common that one prominent Japanese chef said restaurant diners no longer liked food without it.

Ajinomoto began marketing MSG in China in 1918, but it ran into resistance from some who saw it as a symbol of Japanese imperialism. Chinese companies developed their own brands of the additive, often marketing it specifically as a vegetarian product appropriate for people who periodically abstained from meat.

In the United States of the 1930s and ‘40s, white Americans were beginning to visit Chinese restaurants, where the use of MSG was probably widespread. At the same time, Ajinomoto made its way into processed American foods like Campbell’s soup. While MSG never caught on as a home kitchen ingredient in the U.S. the way it did in Japan and China, its role in the industrialized food system here was huge. It was common, for example, to find MSG in frozen and canned foods across the country.

Then came the 1960s, with the publication of Silent Spring and new studies warning about possible carcinogenic effects of artificial sweeteners. Americans increasingly questioned the use of food additives, including MSG. The white powder was tied to “Chinese Restaurant Syndrome,” a set of symptoms including numbness and palpitations some people experienced after eating at Chinese restaurants in the U.S. Concerns about the health effects of MSG emerged in Japan as well.

In response, Ajinomoto transformed its marketing, veering away from the idea of a scientifically formulated product and toward natural imagery. At the same time, it sponsored research that suggested umami was a previously unrecognized fifth basic taste. The idea, Sand writes, was to push back against “Bad Science” on chemical additives using “Good Science” focused on flavor.

While some studies have suggested real health hazards from MSG, the scientific consensus today is that the stuff is probably safe. But whether we like the idea of eating it probably still depends on whether we see it as a scientifically engineered “chemical” or a source of naturally delicious umami.