Is MSG Full of Sugar? Debunking the Myth About Monosodium Glutamate

October 20, 2025 •

4 min read

Despite common misconceptions, monosodium glutamate (MSG) does not contain sugar. This popular flavor enhancer is chemically and nutritionally distinct from sugar, offering a savory 'umami' taste rather than sweetness. This article clarifies the composition of MSG and debunks the myth, providing an accurate look at what this ingredient is and how it affects diet and nutrition.

Quick Summary

MSG is not sugar and contains no carbohydrates. It is the sodium salt of an amino acid used for its savory umami flavor, not sweetness. The myth likely stems from its fermentation process using sugar sources, though the final product is a salt, not a sugar. MSG can even help reduce sodium in foods without sacrificing taste.

Key Points

MSG is NOT sugar: Monosodium glutamate is the sodium salt of glutamic acid, an amino acid, and does not contain any carbohydrates or sugar.
Umami, not sweet: MSG provides a savory, umami flavor that enhances the natural taste of food, unlike sugar, which provides sweetness.
Fermentation process is misleading: While MSG is commercially produced by fermenting sugar beets, sugarcane, or corn, the fermentation process converts the sugar into glutamic acid, so the final product contains no sugar.
Less sodium than salt: MSG contains approximately one-third the amount of sodium as table salt, making it a useful tool for reducing sodium content without sacrificing flavor.
Decades of research confirm safety: Global food safety authorities, including the FDA, have deemed MSG to be 'generally recognized as safe' (GRAS), with no conclusive evidence of adverse effects in the general population.
Natural glutamate is abundant: Glutamate, the key component of MSG, is found naturally in many everyday foods like tomatoes, mushrooms, and aged cheeses.

What is Monosodium Glutamate (MSG)?

Monosodium glutamate, or MSG, is a flavor enhancer widely used in food across the globe. It is the sodium salt of glutamic acid, an amino acid found naturally in many foods like tomatoes, mushrooms, aged cheeses, and cured meats. Japanese chemist Kikunae Ikeda first isolated glutamate from seaweed broth in 1908 and identified its distinct savory taste, which he named "umami". The MSG we use today is typically produced through the fermentation of plant-based ingredients.

The Fermentation Process Explained

The confusion about MSG containing sugar likely arises from how it is commercially produced. Modern MSG is made via a fermentation process similar to making yogurt or vinegar. Microbes are used to ferment sugar sources such as sugarcane, sugar beets, corn, or cassava. These microbes consume the sugar and convert it into glutamic acid. This glutamic acid is then neutralized with sodium to form monosodium glutamate, the final crystalline product that contains no carbohydrates or sugar.

Chemical and Nutritional Breakdown

To understand why MSG is not sugar, it's essential to look at its chemical composition and nutritional profile. The chemical formula for MSG is C5H8NO4Na. In contrast, a common sugar like glucose is C6H12O6. As the formulas show, MSG is an amino acid salt, while sugar is a carbohydrate. This fundamental difference means they are metabolized and taste completely differently.

Nutritional Facts: MSG vs. Sugar

A direct comparison of the nutritional content of MSG and sugar highlights their differences. According to nutritional data, pure MSG contains zero grams of total carbohydrates, zero grams of sugar, and zero grams of protein. It does, however, contain sodium, at about one-third the amount found in table salt by weight, and is sometimes used as a tool to help reduce overall sodium content in recipes. Pure sugar, on the other hand, is a carbohydrate with a significant calorie count, primarily from its sugar content.

The Umami Flavor Profile

MSG's flavor contribution is purely umami, the fifth basic taste alongside sweet, sour, salty, and bitter. Umami provides a pleasant, savory, and satisfying depth to food. It doesn't have a sweet or salty taste on its own but rather enhances the savory notes already present in a dish. Adding MSG to sweet foods, for example, would do little to improve their flavor. This is in direct contrast to sugar, which activates the sweet taste receptors on the tongue.

Can MSG be used to reduce sodium?

Because MSG provides a savory flavor intensity, it can be used to reduce the amount of table salt in recipes without sacrificing taste. This is particularly beneficial for individuals managing their sodium intake for health reasons. Since MSG contains approximately 12% sodium, compared to table salt's 39%, using a combination of the two can significantly lower a dish's overall sodium count while still delivering a satisfying flavor profile.

A History of Misinformation

The negative reputation surrounding MSG is largely based on anecdotal accounts from the 1960s, rather than scientific evidence. The so-called "Chinese Restaurant Syndrome," which linked MSG to symptoms like headaches and flushing, has been widely debunked by decades of research. Unfortunately, this early misinformation, often fueled by racist biases, created lasting myths about the ingredient, including the false notion that it is a harmful or sugar-laden additive. Reputable health organizations, including the U.S. Food and Drug Administration (FDA) and the World Health Organization (WHO), classify MSG as "generally recognized as safe" (GRAS) when consumed in normal amounts.

Natural Sources of Glutamate

Understanding that glutamate is a naturally occurring amino acid helps demystify MSG. It's not a strange, laboratory-created compound but a concentrated version of something found in many everyday ingredients.

Tomatoes: Ripe tomatoes and tomato paste are excellent natural sources of glutamate.
Aged Cheeses: Cheeses like Parmesan and Roquefort contain high levels of glutamate, contributing to their savory, deep flavor.
Mushrooms: Dried shiitake mushrooms and other varieties are packed with natural glutamate.
Meat and Fish: Proteins such as beef, chicken, and shellfish contain naturally occurring glutamate.
Fermented Products: Soy sauce, miso, and fish sauce derive their savory flavor from natural glutamate created during fermentation.

Comparison Table: MSG vs. Table Sugar


Feature	Monosodium Glutamate (MSG)	Table Sugar (Sucrose)
Chemical Type	Sodium salt of an amino acid	Carbohydrate (Disaccharide)
Primary Taste	Umami (Savory)	Sweet
Caloric Content	0 kcal/serving	16 kcal/teaspoon [Search Engine]
Carbohydrates	0g per serving	4g per teaspoon [Search Engine]
Source	Fermentation of starch or sugar sources	Extracted from sugarcane or sugar beets [Search Engine]
Metabolism	Metabolized as an amino acid	Metabolized as a simple carbohydrate (glucose and fructose)

Conclusion

To answer the question, "Is MSG full of sugar?" with a definitive no, it is crucial to separate fact from fiction. MSG is not a sugar, nor does it contain sugar. It is the sodium salt of glutamic acid, an amino acid that imparts a savory umami taste to food. The myth is likely tied to its manufacturing process, which uses sugar sources for fermentation, but the final product is entirely different. MSG is a safe and effective flavor enhancer that contains no carbohydrates or sugar and can even be used as a tool to help reduce the sodium content of a dish. For those aiming to maintain a balanced and healthy diet, MSG can be included without concern for its sugar or carbohydrate content.

Visit MSGdish.com for more information on the science behind MSG and its role in cooking.

Frequently Asked Questions

Pure MSG contributes a negligible number of calories to food. A typical serving contains zero carbohydrates, zero sugar, and zero fat, so its caloric impact is minimal.

No, MSG is not linked to weight gain in the same way as sugar. Since it contains no sugar or carbohydrates, it does not contribute to weight gain by raising blood sugar levels or adding significant calories. Any perceived link is likely due to its use in highly processed foods, which are often high in calories regardless of MSG content.

Table salt is sodium chloride, which provides a purely salty taste. MSG is monosodium glutamate, the sodium salt of an amino acid that provides a savory, umami taste. MSG also contains significantly less sodium than table salt.

No, MSG is not bad for diabetics for this reason. The fermentation process converts the sugar into an amino acid salt, and the final MSG product contains no sugar. Therefore, it does not impact blood sugar levels.

No, MSG does not have a sweet taste. It is specifically used to enhance the savory, or umami, flavor of foods. It has little to no effect on sweet or bitter tastes.

The commercial production of MSG uses a fermentation process, similar to making yogurt or wine. Microorganisms consume a carbohydrate source like sugar and convert it into glutamic acid, which is then processed into the final MSG salt.

No, you cannot replace sugar with MSG. They serve entirely different purposes in cooking. MSG enhances savory flavors, while sugar adds sweetness. Using MSG in a dessert recipe would not be effective.