Did you know that there is a chemical in food that triggers your brain to release pleasure-inducing chemicals? That chemical is glutamate, and it’s responsible for the deliciousness of many foods.
But what exactly is glutamate? And why does eating it make you feel so good? Let’s take a look at this important chemical!
Glutamate is a neurotransmitter that’s found in many types of food—one of the most common being chicken. When your brain detects glutamate, it signals your body to produce endorphins, which make you feel happy. This explains why eating something with lots of glutamate can make us feel so good!
It’s also worth noting that there are some people who are sensitive to glutamate. This means that if they eat too much of it, their brains may become overwhelmed by endorphins and cause them to experience negative side effects like headaches or nausea. If you suspect that you might be one of these people, talk to your doctor about getting tested for sensitivity before you start eating large amounts of food with high levels of glutamate.
Food With Glutamate
Glutamate is an amino acid that is produced in the body and also occurs naturally in many foods. Monosodium glutamate (MSG) is the sodium salt of glutamic acid and is a common food additive. MSG is made from fermented starch or sugar and is used to enhance the flavor of savory sauces, salad dressings, and soups.
Both natural glutamate and monosodium glutamate are metabolized in the body using the same processes. Even though glutamate exists naturally in the body and healthy foods, many people worry that excess glutamate consumption can lead to health problems.
Why You Should Avoid Glutamate
Dietary glutamate has been examined in numerous studies to determine if it is safe to consume regularly. The relatively high glutamate levels in some traditional diets suggest that it is a safe food additive. However, anecdotal and scientific evidence indicates that high levels of glutamate and MSG consumption cause adverse health effects.
Glutamate consumption has been linked to the following:
Countless anecdotal reports have claimed that eating Chinese food high in MSG causes headaches. This sudden onset of heart palpitations and headache has been called “Chinese Restaurant Syndrome,” and the validity of these claims have been examined in several studies. One study concluded that MSG injures brain cells, and the resulting cellular inflammation leads to a headache.
Increased Blood Pressure
Another group of researchers looked at how the body responds to one 150mg dose of MSG, observing pain sensitivity and blood pressure. Not only did the test subjects experience headaches and increased pain sensitivity, but also a short-term spike in blood pressure levels.
These observed effects of MSG consumption suggest that people with high blood pressure should avoid excessive MSG dietary intake.
Ingestion of MSG has been associated with increased insulin resistance and reduced glucose tolerance in animal studies. These effects can lead to obesity, although researchers have not yet determined if humans experience the same results. The same studies demonstrated that the ingestion of MSG also disrupts energy metabolism and causes inflammation and liver damage.
MSG consumption has been linked to increased pain sensitivity and pain intolerance, which has prompted investigations into MSG’s role in psychiatric disorders. There is strong evidence that MSG is a factor in schizophrenia, and it has been associated with anxiety, stress, and depression.
glutamate food chart
Hundreds of ingredients are added to foods during processing to enhance the flavor of the final product.
Monosodium glutamate, commonly known as MSG, is one of the most controversial food additives approved for use by the Food and Drug Administration (FDA).
While it’s “generally recognized as safe” (GRAS) to be used in the food supply by regulatory agencies, some research shows that it may negatively affect health, which is why many people choose to avoid it (1Trusted Source).
This article explains what MSG is, what foods it’s typically added to, and what the research says about possible health implications.
What is MSG?
MSG is a popular flavor enhancer derived from L-glutamic acid, a naturally occurring amino acid that’s necessary for the creation of proteins (2).
Aside from being used as a food additive, MSG occurs naturally in certain foods, including tomatoes and cheeses (3).
It was first identified as a flavor enhancer by Japanese researchers in 1908 and has since become one of the most widely used additives in food production (3).
Today, it can be found in a number of processed products, from fast food to canned soups.
MSG boosts the flavor of foods by stimulating taste receptors and has been shown in research studies to increase the acceptance of particular flavors. Adding MSG to foods results in an umami taste, which is characterized as savory and meaty (4Trusted Source).
This popular additive has been deemed GRAS by the FDA, though some experts argue that it can have potentially dangerous side effects, particularly when consumed on a long-term basis (5Trusted Source).
The FDA mandates that MSG must be labeled by its usual name of monosodium glutamate when used as an ingredient in food. Foods that naturally contain MSG, such as tomato products, protein isolates, and cheeses, aren’t required to list MSG as an ingredient (6).
In other countries, MSG is classified as a food additive and may be listed by the E-number E621 (7).
Here are 8 foods that commonly contain MSG.
1. Fast food
One of the best-known sources of MSG is fast food, particularly Chinese food.
In fact, MSG symptom complex is a condition characterized by symptoms including headache, hives, swelling of the throat, itching, and belly pain experienced by some people shortly after consuming MSG-laden Chinese food (8Trusted Source).
Although many Chinese restaurants have stopped using MSG as an ingredient, others continue to add it to a number of popular dishes, including fried rice.
MSG is also used by franchises like Kentucky Fried Chicken and Chick-fil-A to enhance the flavor of foods.
For example, Chick-fil-A’s Chicken Sandwich and Kentucky Fried Chicken’s Extra Crispy Chicken Breast are just some of the menu items that contain MSG (9, 10).
2. Chips and snack foods
Many manufacturers use MSG to boost the savory flavor of chips.
Consumer favorites like Doritos and Pringles are just some of the chip products that contain MSG (11, 12).
Aside from being added to potato chips, corn chips, and snack mixes, MSG can be found in a number of other snack foods, so it’s best to read the label if you want to avoid consuming this additive.
3. Seasoning blends
Seasoning blends are used to give a salty, savory taste to dishes like stews, tacos, and stir-fries.
MSG is used in many seasoning blends to intensify taste and boost the umami flavor cheaply without adding extra salt (13Trusted Source).
In fact, MSG is used in the production of low sodium items to increase flavor without the addition of salt. MSG can be found in many low sodium flavoring products, including seasoning blends and bouillon cubes (14).
Additionally, MSG is added to some meat, poultry, and fish rubs and seasonings to enhance the palatability of foods.
4. Frozen meals
Although frozen meals can be a convenient and cheap way to put food on the table, they often contain a host of unhealthy and potentially problematic ingredients, including MSG.
Many companies that make frozen dinners add MSG to their products to improve the savory flavor of the meal (16Trusted Source).
Other frozen products that often contain MSG include frozen pizzas, mac and cheese, and frozen breakfast meals.
Canned soups and soup mixes often have MSG added to them to intensify the savory flavor that consumers crave.
Perhaps the most popular soup product that contains this controversial additive is Campbell’s chicken noodle soup (17).
Many other soup products, including canned soups, dried soup mixes, and bouillon seasonings, can contain MSG, making it important to check individual product labels.
6. Processed meats
Processed meats like hot dogs, lunch meats, beef jerky, sausages, smoked meats, pepperoni, and meat snack sticks can contain MSG (18).
Aside from being used to enhance taste, MSG is added to meat products like sausage to reduce the sodium content without changing the flavor (19Trusted Source).
One study found that replacing sodium with MSG in pork patties enhanced the salty flavor and acceptability of the product without negatively affecting taste (19Trusted Source).
Condiments like salad dressing, mayonnaise, ketchup, barbecue sauce, and soy sauce often contain added MSG (18).
In addition to MSG, many condiments are packed with unhealthy additives like added sugars, artificial colorings, and preservatives, so it’s best to purchase products that are made with limited, whole food ingredients whenever possible.
If you’re concerned about using MSG-containing condiments, consider making your own so that you have complete control over what you’re consuming. For starters, you can try out these delicious and healthy salad dressing recipes.
8. Instant noodle products
A staple for college students around the world, instant noodles provide a quick, filling meal for those on a budget.
However, many manufacturers use MSG to boost the savory flavor of instant noodle products. Plus, instant noodles are typically made from unhealthy ingredients and are loaded with added salt, refined carbs, and preservatives that can harm your health.
Instant noodle consumption has been associated with increased heart disease risk factors, including elevated blood sugar, cholesterol, triglyceride, and blood pressure levels (20Trusted Source).
Is MSG harmful?
While research is far from conclusive, some studies have suggested that consuming MSG may lead to negative health outcomes.
For example, MSG consumption has been linked to obesity, liver damage, blood sugar fluctuations, elevated heart disease risk factors, behavioral problems, nerve damage, and increased inflammation in animal studies (5Trusted Source).
Some human research has demonstrated that consuming MSG may promote weight gain and increase hunger, food intake, and your risk of metabolic syndrome, a group of symptoms that raises your risk of chronic conditions like heart disease and diabetes (3).
For example, a study in 349 adults found that those who consumed the most MSG were much more likely to have metabolic syndrome than those who consumed the least, and that every 1 gram increase of MSG per day significantly increased the chances of being overweight (21Trusted Source).
However, larger, well-designed studies are needed to confirm this potential link (22Trusted Source).
There’s also some evidence that MSG increases hunger and may lead you to eat more at meals. However, current research suggests a more complex relationship between MSG and appetite, with some studies finding that MSG may even decrease intake at meals (23Trusted Source).
Although research is mixed on how MSG may affect overall health, it’s clear that consuming high doses of 3 grams or higher of MSG per day is likely to lead to adverse side effects, including headache and increased blood pressure (24Trusted Source).
For reference, it’s estimated that the average consumption of MSG in the United States and the United Kingdom is around 0.55 grams per day, while intake of MSG in Asian countries is around 1.2–1.7 grams per day (5Trusted Source).
Although it’s possible, consuming 3 grams of MSG or more per day is unlikely when eating normal portion sizes.
However, certain individuals who have a sensitivity to MSG may experience side effects like hives, swelling of the throat, headache, and fatigue after consuming smaller amounts, depending on individual tolerance (8Trusted Source, 24Trusted Source).
Still, a review of 40 studies found that, overall, studies that have linked MSG with adverse health effects are of poor quality and have methodological flaws, and that strong clinical evidence of MSG hypersensitivity is lacking, highlighting a need for future research (24Trusted Source).
While evidence of MSG sensitivity is lacking, many people report that consuming this additive leads to adverse side effects.
If you think you may have a sensitivity to MSG, it’s best to avoid the products listed on this page and always check labels for added MSG.
Furthermore, even though the safety of MSG is debated, it’s clear that foods that commonly contain MSG, like chips, frozen meals, fast food, instant noodles, and processed meats, aren’t good for overall health.
Therefore, cutting out MSG-laden products will likely benefit you in the long run — even if you aren’t sensitive to MSG.
Some studies have associated MSG with negative health outcomes, including obesity and metabolic syndrome. However, more research is needed to substantiate these findings.
The bottom line
MSG is a controversial food additive that’s found in a wide variety of products. It’s commonly added to chips, frozen dinners, fast food, instant noodles, and many other processed foods to enhance flavor.
Although some studies have linked MSG consumption with negative health outcomes, more research is needed to fully understand the potential effects that consuming MSG may have on both short- and long-term health.
If you feel that you’re sensitive to MSG, it’s best to avoid products that contain it. Be sure to always read food labels to ensure your items are free of MSG.
Is MSG Truly Unhealthy? All You Need to Know
- What it is
- What the research says
- Food sources
- Bottom line
Monosodium Glutamate (MSG) is a flavor enhancer that has been widely used for roughly 100 years (1Trusted Source).
In addition to being naturally present in certain foods, it’s a common food additive in Chinese recipes, canned vegetables and soups, and other processed goods.
For years, MSG has been viewed as an unhealthy ingredient. However, newer research questions the accuracy of its purported adverse effects on human health.
This article examines MSG and what current evidence has to say about its health effects.
What is MSG?
MSG is short for monosodium glutamate.
It’s a flavor enhancer derived from L-glutamic acid, which is naturally present in many foods. L-glutamic acid is a nonessential amino acid, meaning that your body can produce it by itself and doesn’t need to get it from food (1Trusted Source).
MSG is a white, odorless, crystalline powder commonly used as a food additive. In the food industry, it’s known as E621. It dissolves easily in water, separating into sodium and free glutamate (2Trusted Source).
It’s made by fermenting carb sources like sugar beet, sugar cane, and molasses (3Trusted Source).
There’s no chemical difference between the glutamic acid found naturally in some foods and that found in MSG. This means your body can’t differentiate between the two types (3Trusted Source, 4Trusted Source, 5Trusted Source).
MSG has a specific taste known as umami — the fifth basic taste alongside sweet, sour, salty, and bitter. Umami has a meaty flavor that refers to the presence of proteins in food (2Trusted Source, 6Trusted Source).
Besides MSG, other umami compounds include inosine 5’-monophosphate (IMP) and guanosine 5’-monophosphate (GMP) (1Trusted Source).
MSG is popular in Asian cooking and used in various processed foods in the West. It’s estimated that people’s average daily intake is 0.3–1.0 grams (1Trusted Source, 7Trusted Source).
The flavor-enhancing effects of MSG are due to its umami taste, which induces salivary secretion. In other words, umami flavors make your mouth water, which can improve the taste of food (6Trusted Source).
What’s more, studies show that umami substances can lower the desire to salt foods. Salt is another flavor enhancer (6Trusted Source, 8Trusted Source).
In fact, some research postulates that replacing some salt with MSG can reduce people’s sodium intake by approximately 3% without sacrificing flavor (1Trusted Source, 8Trusted Source).
Similarly, MSG may be used as a salt substitute in low sodium products like soups, prepackaged meals, cold meats, and dairy products (8Trusted Source).
MSG is derived from L-glutamic acid, an amino acid found in your body and many foods. It’s a popular food additive used to enhance flavor. It can be used to reduce overall sodium intake when used in place of salt.
Why do people think it’s harmful?
MSG got its bad reputation in the 1960s when Chinese-American doctor Robert Ho Man Kwok wrote a letter to the New England Journal of Medicine explaining that he got sick after consuming Chinese food.
He wrote that he believed his symptoms could have resulted from consuming either alcohol, sodium, or MSG. This sparked a host of misinformation about MSG, which was likely related to then-present biases against Chinese immigrants and their cuisine (9Trusted Source).
The letter led to the designation of Kwok’s symptoms as the “Chinese restaurant syndrome,” which later became the “MSG symptom complex” (MSC) (1Trusted Source).
Later on, numerous studies backed MSG’s bad reputation, stating that the additive was highly toxic (1Trusted Source).
However, current evidence questions the accuracy of previous research for several reasons, including (1Trusted Source):
- a lack of adequate control groups
- small sample sizes
- methodological flaws
- a lack of dosage accuracy
- the use of extremely high doses that far exceed those consumed in typical diets
- the administration of MSG via routes with little to no relevance to oral dietary intakes, such as injections
Today, health authorities like the Joint FAO/WHO Expert Committee on Food Additives (JECFA), the Food and Drug Administration (FDA), and the European Food Safety Association (EFSA) consider MSG to be generally recognized as safe (GRAS) (1Trusted Source, 4Trusted Source).
They have also determined an acceptable daily intake (ADI) of 14 mg per pound (30 mg per kilogram) of body weight per day. This is far more than the amount you’d typically ingest following a normal diet (1Trusted Source, 4Trusted Source).
While racial biases and older research implied that MSG was a toxic additive, current evidence and health authorities recognize it as safe.
Older vs. current research on MSG’s health effects
MSG has been linked to obesity, metabolic disorders, brain toxicity, and MSC. Here’s what the current research has to say about these purported downsides (7Trusted Source).
Effect on energy intake
Older evidence states that by making food taste better, MSG disrupts the signaling effect of the hormone leptin in your brain. Leptin is in charge of telling your body that you’ve had enough to eat. In turn, this is said to increase your calorie intake (7Trusted Source, 10Trusted Source).
However, the current data on MSG’s effects on energy intake is contradictory. Some studies have found that it may reduce appetite, while others support the idea that its flavor-enhancing properties could lead to overeating (1Trusted Source, 6Trusted Source).
The contradictory results might have to do with the nutritional profile of a meal. For example, eating MSG-enhanced, high protein meals has been linked to increased feelings of fullness, while this link hasn’t been observed with high carb meals (1Trusted Source).
However, this could also be because protein is the most filling macronutrient — it might not have anything to do with the MSG content (1Trusted Source).
Other studies note that eating MSG-enriched meals could cause you to eat fewer calories at subsequent meals and reduce your energy intake from non-MSG-enriched and savory, high fat foods (1Trusted Source, 11Trusted Source).
Ultimately, more research on the connection between MSG and energy intake is needed.
Obesity and metabolic disorders
MSG has been associated with an increased risk of metabolic disorders, primarily due to animal studies that have linked the additive to insulin resistance, high blood sugar levels, and diabetes (2Trusted Source, 7Trusted Source).
However, previous research has used imprecise methods for determining MSG consumption, such as injections instead of oral doses. This could lead to effects on the brain that are not associated with dietary intake (1Trusted Source, 2Trusted Source, 12Trusted Source).
What’s more, the current data is contradictory. For instance, newer animal studies have found an association between umami substances and anti-obesity effects. In contrast, other animal and human studies show no effect on body weight (6Trusted Source, 12Trusted Source).
While it appears that typical dietary MSG intakes are unlikely to influence body weight or fat metabolism, more human studies are needed (12Trusted Source).
Effect on brain health
Glutamate plays many important roles in brain function. For starters, it acts as a neurotransmitter — a chemical substance that stimulates nerve cells to transmit signals (1Trusted Source, 2Trusted Source).
Some studies claim that MSG can lead to brain toxicity by causing excessive glutamate levels in the brain to overstimulate nerve cells, resulting in cell death (2Trusted Source, 7Trusted Source).
However, dietary glutamate likely has little to no effect on your brain, as almost none of it passes from the gut into the blood or crosses the brain barrier (1Trusted Source, 4Trusted Source, 12Trusted Source, 13Trusted Source).
In fact, research shows that once ingested, MSG is completely metabolized in your gut. From there, it either serves as an energy source, is converted to other amino acids, or is used in the production of various bioactive compounds (1Trusted Source, 4Trusted Source).
Overall, no compelling evidence suggests that MSG alters brain chemistry when consumed in normal amounts.
Some people may be sensitive
Some people may experience adverse effects from consuming MSG due to a condition called MSG symptom complex (MSC). It’s estimated to affect less than 1% of the general population (1Trusted Source).
MSC is characterized by symptoms similar to those described by Dr. Kwok in his letter. They include weakness, flushing, dizziness, headache, numbness, muscle tightness, difficulty breathing, and even the loss of consciousness (1Trusted Source).
The threshold dose that causes short-term and mild symptoms in sensitive people appears to be 3 or more grams of MSG without food (1Trusted Source, 5Trusted Source).
Keep in mind, though, that a 3-gram dose is a high one. A typical serving of an MSG-enriched food contains less than half a gram of the additive, so consuming 3 grams at one time is highly unlikely (5Trusted Source).
Current evidence debunks most of the beliefs that consider MSG harmful or dangerous. However, in some cases, research findings are contradictory, and further studies in humans are needed.
Common foods that contain MSG
MSG is naturally present in many different foods, especially those that are high in protein. It’s also added to ingredients and other foods during processing (1Trusted Source, 4Trusted Source).
Common foods that contain MSG are (1Trusted Source, 6Trusted Source, 14, 15):
- Animal-based protein: chicken, beef, salmon, mackerel, scallops, crab, shrimp
- Cheese: Parmesan, Emmenthal, cheddar, Roquefort
- Vegetables: tomatoes, onions, cabbage, green peas, spinach, mushrooms, broccoli
- Processed meats: pepperoni, bacon, pastrami, sausages, salami
- Sauces and dressings: soy sauce, ketchup, mustard, mayonnaise, barbecue sauce, salad dressings
- Premade and packaged foods: canned soups, canned tuna, frozen meals, crackers, potato chips, flavored snacks
- Condiments: seasoning blends, rubs
Additionally, fast-food chains like McDonald’s, Chick-fill-A, and KFC use MSG to season menu items like fried chicken, chicken nuggets, and fries (16, 17, 18).
MSG is naturally present in many foods, including some cheeses, meats, and vegetables. It’s also added to some processed and fast-food items.
The bottom line
MSG is a flavor-enhancing additive that’s also naturally present in many protein-rich foods, cheeses, and vegetables.
Although it was considered a toxic ingredient during the 1960s, current evidence has dispelled that myth, indicating that MSG is safe when consumed in moderate amounts.
Still, you shouldn’t eat excessively large doses or consume it if you experience adverse reactions.