There is much debate over MSG, a flavor enhancer, linked to a host of health issues. There are dangers of hidden MSG, which may appear in many of our favorite “healthy” foods, without showing up on the label.
Health Issues Linked to MSG
- fatty liver3
- high insulin and blood sugar4
- high cholesterol3
- metabolic syndrome4
- high blood pressure
- disturbances in the gut-brain connection5
- neurological and brain health issues6
- much more
What is MSG?
In the 1960s, the phrase Chinese Restaurant Syndrome was coined by an article in The New England Journal of Medicine. Twenty minutes after eating Chinese food, some very sensitive people would experience tingling, brain fog, numbness, chest pressure, and pain.
Monosodium Glutamic Acid (MSG) refers to a chemical extract: glutamic acid is isolated, bound to a sodium molecule, and purified into a white powder, which is added to foods as a flavor enhancer.
MSG can be an excitotoxin, which means it amps up and stimulates sensory nerves, making food enhanced and tastier. As a flavor enhancer, active forms of MSG or glutamic acid are called D-glutamic acid and L-glutamic acid, usually containing other toxic byproducts.
When proteins are ingested in their natural state, the stomach breaks these proteins down into L-glutamic acid. When proteins are processed, heated, hydrolyzed, or fermented, as in MSG or proteins powders, veggie proteins, etc., they break down into both D– and L-glutamic acid.7
This suggests it is the D-glutamic acid that is the culprit causing MSG reactions. But D-glutamic acid is tasteless and benign, according to Dr. Darren Gay, PhD, a researcher who specialized in purified amino acids. The more likely cause, according to Dr. Gay, are the toxic byproducts of processing and an inability to handle L-glutamic acid.
When proteins are manufactured, processed, or fermented, they will not only produce D- and L-glutamic acids, they will produce a host of toxic byproducts that may also be a factor in MSG symptoms.
Toxic Byproducts of MSG + Other Manufactured, Processed, or Fermented Foods
- pyroglutamic acid
- mono and dichloro propanols (which are carcinogenic)
- heterocyclic amines (which are carcinogenic)
- other unwanted byproducts (impurities)7
MSG, Amino Acids + the Nervous System
It seems that the combination of processed L-glutamic acid, possibly D-glutamic acid, along with toxic byproducts is the cause or an exacerbation of MSG symptoms.
This is why certain people who are “MSG sensitive” cannot tolerate MSG or processed protein products that have been denatured in the manufacturing process. This can include any protein that has been broken down, heated, or processed—found in most packaged foods.
L-glutamic acid found in processed protein foods, as well as when proteins are naturally digested through the stomach, is a stimulating molecule that activates taste and nerves.
Very high dosages of L-glutamic acid can overstimulate the nervous system.
Fortunately, the body highly regulates the amount of L-glutamic acid allowed into the bloodstream. The body needs it and if there is not enough, the body will use other amino acids to manufacture its own glutamic acid. This is why glutamic acid is a non-essential amino acid—the body can make its own.
This suggests the importance of glutamic acid for the function of the body and nervous system.7 It also suggests the importance of the health and integrity of the intestinal skin as a protective barrier from excess or overwhelming amounts of amino acids that can overexcite the nervous system.
It is true that when proteins are processed, they can be denatured or flip into being a D- or L-glutamic acid. Some experts believe D-glutamic acid that is the culprit for toxicity reactions to MSG because processing proteins has been shown to increase D- not L-glutamic acid. But, as I mentioned, the consensus seems to be that the cause of MSG symptoms is the toxic combination of excess L-glutamic acid and excess toxic byproducts.7
The form of glutamic acid called L-glutamic acid, which naturally occurs in many foods and proteins in the body is considered a nontoxic form by many experts.
The average human has 4.4 pounds of L-glutamic acid in the body and there are no reactions. Glutamic acid is a main component of proteins. It is found in meat, eggs, poultry, milk, eggs, cheese, fish, and even wheat. It is also found in most grains, beans, vegetables, mushrooms, fruits, and seaweed.
In these natural forms, glutamic acid is bound to other proteins in chains of amino acids or proteins. The process of freeing glutamic acid from the protein chains during the human digestion of proteins is generally not a problem.
When glutamic acid is freed from the amino acid chain during processing, there seems to be concerns.
We RecommendThe Dangers of Common Protein Sources
Dangers of Hidden MSG
So, avoiding MSG should be easy right? As a flavor enhancer, MSG is required by the FDA to be listed in the ingredients. However, as a processing agent, which is very common in many food products, MSG does not require labeling. This exposes many of us to L- and D-glutamic acid and its toxic byproducts on a regular basis.
Interestingly, only a small percentage of the population reacts to MSG, and much seems to depend on the amount of MSG one is exposed to and how sensitive one’s intestinal wall is to toxins.
In a healthy body, proteins are broken down in the stomach and small intestine by hydrochloric acid (HCl) and digestive enzymes. The body’s digestive tract controls how much glutamic acid is freed up from the protein chain, but free L-glutamic acid absorption is highly limited and most of it is passed off as waste through the intestinal tract.
If this type of free glutamic acid is rapidly absorbed into the bloodstream because of a breakdown of intestinal skin, it can trigger a neuroexcitatory toxic response in the body.
D-glutamic acid is made by processing food and the body does not seem to recognize it.
How To Avoid Non-Labeled MSG
Without a doubt, we should be reading labels and avoiding any food with MSG. Even if you do not seem to be sensitive to it, MSG is an irritant or neurotoxin and can damage the intestinal wall over time and create other problems down the road.
To avoid non-labeled MSG used in very small quantities as a processing aid, all processed foods must be avoided. This includes many health foods, such veggies burgers, turkey sausages, textured or hydrolyzed proteins, and processed protein powders.
Some, but for sure not all, health food companies go through the trouble of avoiding processed proteins in such a way that avoids production of excess L-glutamic acid, D-glutamic acid, and toxic by-products.
The key is to avoid large exposures to MSG and especially packed protein products. Choose fresh, non-processed foods as often as possible.
That said, since a small amount of L- and D-glutamic acid is incredibly hard to avoid, the most logical thing to do is continue to support the health of the intestinal skin so that it continues to act as a protective barrier against toxins. If the inner skin breaks down, numerous undigested toxins can enter the bloodstream and lymph and become irritants, toxins, allergens, triggering similar symptoms to MSG sensitivity. Non-celiac gluten sensitivity is a perfect example.
My 3 Favorite Ayurvedic Herbs to Support Intestinal Skin from Irritants Such as MSG
Hidden Names for MSG + Free Glutamic Acid
Ingredients that always contain processed free glutamic acid7
- Glutamic Acid (E 620)
- Glutamate (E 620)
- Monosodium Glutamate (E 621)
- Monopotassium Glutamate (E 622)
- Calcium Glutamate (E 623)
- Monoammonium Glutamate (E 624)
- Magnesium Glutamate (E 625)
- Natrium Glutamate
- Yeast Extract
- Anything “hydrolyzed”
- Calcium Caseinate
- Sodium Caseinate
- Yeast Food
- Yeast Nutrient
- Autolyzed Yeast
- Textured Protein
- Soy Protein Concentrate
- Soy Protein Isolate
- Whey Protein Concentrate
- Whey Protein Isolate
Ingredients that often contain or produce processed free glutamic acid7
- Carrageenan (E 407)
- Bouillon and broth
- Any “flavors” or “flavoring”
- Citric acid, Citrate (E 330)
- Anything “ultra-pasteurized”
- Barley malt
- Pectin (E 440)
- Anything “enzyme modified”
- Anything containing “enzymes”
- Malt extract
- Soy sauce
- Soy sauce extract
- Anything “protein fortified”
- Anything “fermented”
Ingredients suspected of containing or creating sufficient processed free glutamic acid to serve as MSG-reaction triggers in HIGHLY SENSITIVE people7
- Corn starch
- Corn syrup
- Modified food starch
- Lipolyzed butter fat
- Rice syrup
- Brown rice syrup
- Milk powder
- Reduced fat milk (skim; 1%; 2%)
- Most things labeled “Low Fat” or “No Fat”
- Anything labeled “Enriched”
- Anything labeled “Vitamin Enriched”
Avoiding MSG may be harder than it first appears. Do what you can and treat your gut right!