What Is MSG In Food, And Is It Dangerous?

Certain food additives are universally known to be unhealthy. For example, artificial food coloring such as Red No. 40, Blue No. 1, and Yellow No. 5. provide no nutritional value and may be toxic to human health. 

Other common food additives that are used to impart flavor, increase shelf life, or improve texture are more controversial, with some evidence suggesting potential adverse health effects. A common example is MSG, also known as monosodium glutamate.

Given the prevalence of MSG in many common food products, it’s important to understand if MSG is dangerous. But, what is MSG in food, and what is MSG used for? And is MSG dangerous?

MSG has a deep umami and salty flavor that is said to increase the palatability or taste appeal of food products, creating a desirable craveability.

In this article, we will discuss what MSG is used for in food, what MSG is made of, and most importantly, whether MSG is safe to eat or should be avoided.

More specifically, we will cover: 

• What Is MSG and What Is MSG Made Of?

• Is MSG In Food Safe?

• Does MSG Cause Weight Gain?

• How Do I Know If There Is MSG In My Food?

• Should I Avoid MSG In Food?

Let’s jump in!

What Is MSG and What Is MSG Made Of?

Many people have heard of MSG in food, but they aren’t exactly sure what MSG is.

MSG, which is short for monosodium glutamate, is a flavoring agent or flavor enhancer that has been used in foods for over 100 years. 

MSG is made from an amino acid (the building block of protein) called L-glutamic acid, which is produced by fermenting a source of sugar such as corn, sugar cane, sugar beets, tapioca, or molasses.

It is a white, odorless, crystalline powder that dissolves in water and dissociates into sodium and free glutamate, which is a non-essential amino acid, which means the body can produce it endogenously.

MSG also naturally occurs in foods such as tomatoes, onions, spinach, green peas, cabbage, and broccoli, and cheeses such as Parmesan, cheddar, and Roquefort. Some amount of MSG is also present in animal-based proteins such as beef, chicken, salmon, mackerel, crab, shrimp, and scallops.

However, most MSG in food is typically found as an added ingredient in processed foods such as canned soups, soy sauce, deli meat, pepperoni, salami, pastrami, sausages, ketchup, mustard, barbeque sauce, mayonnaise, salad dressing, canned vegetables, french fries, frozen meals, fast food, chicken nuggets, and Chinese takeout food.

As a flavor enhancer that adds a prominent umami flavor, MSG increases saliva production, meaning that it literally makes your mouth water and, in turn, can improve the way that food tastes. 

Umami is one of the five primary flavors the taste buds can differentiate, along with salty, sweet, sour, and bitter, and it is often present in protein-rich foods like meats, as well as earthy foods like mushrooms and broths.

MSG also has a prominent salty flavor, so it contains about 1/3 as much sodium as regular table salt, so it can be used to enhance the saltiness of food without significantly increasing the daily value of sodium in the food product.

Moreover, studies suggest that foods with a higher umami flavor reduce the desire to add salt to food, so they might be an effective way to reduce sodium intake.

Although MSG is commonly attributed to Chinese food and other Asian-inspired dishes, its use has transcended the Asian food market such that now MSG is added to many commercial food products as mentioned before, such as canned vegetables, soups, salad dressings, deli meats, and restaurant dishes.

Is MSG In Food Safe?

Many people wonder, is MSG dangerous? Or is MSG safe to consume?

Although the U.S. Food and Drug Administration (FDA) has classified MSG as a food ingredient that’s generally recognized as safe, its use is still debated. Therefore, when MSG is added to food products, the FDA requires that the ingredients label reports the usage of MSG. 

According to the Mayo Clinic, the FDA has received many reports about concerning reactions to foods containing MSG over the years, which have since been classified as something termed “MSG symptom complex.” 

Reactions to MSG may include headaches, skin flushing, pressure or tightness in the face, sweating, numbness, tingling or burning in the face or neck, rapid or fluttering heartbeats, nausea, weakness, and chest pain.

With that said, researchers who have tried to pinpoint how these symptoms crop up in response to MSG have not been able to identify any clear or conclusive proof that there is indeed a link between MSG and these symptoms. 

With that said, some people do seem reactive, at least mildly, to MSG, and thus the Mayo Clinic recommends such people avoid foods containing MSG.

According to the Cleveland Clinic, research has debunked the myth that MSG is a toxic ingredient, and evidence suggests that in small doses, there are no significant adverse health effects to eating MSG.

In fact, the FDA reports that MSG sensitivity is generally only an issue when more than 3 grams of MSG is consumed without food, which is highly unlikely in practice since MSG is almost always consumed in food. Furthermore, most food products with added MSG contain less than 0.5 grams per serving.

Additionally, research has confirmed that the human body does not discriminate between glutamate naturally present in food and that added in MSG as a seasoning, meaning that MSG and glutamate are fully and equivalently metabolized by gut cells as an energy source and serve as a key substrate for other important liver metabolites.

Furthermore, when MSG is consumed, it dissociates into sodium and free glutamate, and dietary glutamate has not been found to cross the blood-brain barrier in the body, so it should not affect brain function.

Most nutrition professionals say that people who believe they experience side effects or reactions to MSG—such as flushing and elevated heart rate—are actually responding to other ingredients found in processed foods that contain MSG, such as excessive salt.

Does MSG Cause Weight Gain?

There is some evidence to suggest that excessive MSG intake may be associated with a higher BMI over time. 

With that said, there is little to no evidence to suggest that MSG itself directly affects fat cells, leptin receptors, or other physiological mechanisms associated with weight gain.

However, some researchers say that the fact that MSG improves the taste of food does increase leptin production, which in turn would lead to increased appetite and weight gain.

Essentially, researchers postulate that perhaps that association with higher BMI from higher MSG intake may be due to the fact that MSG increases the palatability or craveability of food, making us eat more of it, which would lead to weight gain.

The umami flavor increases saliva production, which in turn, cleanses the palate and makes us need more of the food to taste it.

With that said, there’s some conflicting research that suggests that the umami flavor imparted by MSG may actually reduce caloric intake and decrease appetite, so your own reaction to MSG may vary.

How Do I Know If There Is MSG In My Food?

The FDA requires MSG to be noted on the food labeling in the United States when it is included as an ingredient in processed foods.

Certain food ingredients also may contain MSG as an integral additive. Examples of ingredients that contain MSG include the following: Maltodextrin, citric acid, barley malt, malted barley, brewer’s yeast, pectin, malt extract, stock, bouillon and broth, carrageenan, oligodextrin, and modified food starch.

Processed foods that contain any of the following naturally-occurring ingredients also contain MSG: hydrolyzed yeast, yeast extract, soy extract, soy isolate, autolyzed yeast, and hydrolyzed vegetable protein.

Should I Avoid MSG In Food?

Ultimately, MSG appears to be safe to consume in moderate amounts and should cause little adverse health reactions, metabolic changes, or weight gain. With that said, if you notice that you experience sensitivity to MSG or have concerns about it, be sure to read food labels and try to avoid processed foods that contain MSG.

It can be difficult to impart an umami flavor at home with your own cooking, but there are certain alternatives, such as earthy mushroom broths, combinations of spices, and products such as packaged umami seasonings.

In general, avoiding processed foods is optimal for health, and since MSG is most often an additive in highly processed foods, choosing to avoid foods with added MSG—such as canned soups, processed meats, fast food, and frozen Chinese food entrees—is ultimately a good choice for overall nutrition.

With that said, consuming some MSG should not be problematic, but speak with your healthcare provider if you have concerns about your reactivity to MSG.

If you are looking for a healthy overall diet to follow, you can check out more of our nutrition guides for some excellent options.

Here are a couple of guides to get you started:

Healthy Diets For Runners

The CICO Diet: The Calories In Calories Out Methos For Weight Loss

Intermittent Fasting