Web Only ArticleJanuary 1, 2008

The MSG Myth

Why the "wonder" spice isn't so wonderful after all.


When monosodium glutamate (MSG) was introduced in this country more than 50 years ago, it was heralded as a miracle food enhancer. It suppressed bitterness, improved flavor, made food smell better, and removed the tinny taste from canned products. There was even talk that it could improve a person's IQ.

American food manufacturers embraced MSG immediately and began adding it to all kinds of food, such as salad dressings, tuna fish, sausages and frozen dinners. Before long, restaurants used it regularly, as did meal programs at airlines, schools and military bases. Even consumers got into the act, sprinkling MSG, under the brand name "Accent," on dishes needing a little zip.

Too Good to Be True?

As MSG became more widely used in the United States, reports began to surface about people's negative reactions to it. In 1968, the New England Journal of Medicine printed a letter from a doctor who experienced numbness at the back of his neck, general weakness and heart palpitations after eating foods containing MSG. Others complained about headaches, nausea, dizziness, disorientation and depression.

The first reports of MSG sensitivity were not taken seriously. Some thought they were psychological. Others concluded that it must be something other than MSG that was making people sick.

Despite piles of evidence, MSG sensitivity remains unacknowledged by many in the food industry and government. To make matters worse, some labels are being altered to hide the fact that the products contain MSG. A few companies have gone so far as to advertise "No MSG" when their products actually contain the substance. The Food and Drug Administration (FDA) has even listed MSG as one of the safest food additives, along with vinegar and salt.

I know from personal experience that the chemical is not as harmless as vinegar or salt. When I ingest a fair amount of MSG, I immediately have nausea, stomach cramps, "spaciness," heart palpitations and a "pins-and-needles" headache, followed the next day by lethargy and overall weakness.

Unfortunately, I'm not alone. Experts estimate that tens of millions of Americans - or as much as 50 percent of the population - may be sensitive to MSG. Relatively few suspect that MSG may be causing their headaches and other symptoms. Fewer still know just how prevalent MSG is.

What is MSG?

More than just a seasoning, MSG is a flavor enhancer. This means it intensifies the existing taste of something rather than altering it. When we taste something, our taste buds transmit electrical signals to the brain. When we taste something with MSG, these electrical signals become more intense.

The principal component of MSG is processed-free glutamic acid. Glutamic acid is one of the amino acids that make up proteins. It occurs naturally in our bodies and in many foods like tomatoes, milk and mushrooms. While some proponents of MSG imply that it is naturally occurring glutamic acid, it is not.

MSG is made in a factory from foods like corn, molasses and wheat, where it is hydrolyzed, autolyzed, modified or fermented using chemicals, bacteria or enzymes. These processes "free" the glutamic acid in the food. In its "free" form, processed glutamic acid lacks the links that natural glutamic acid has to other amino acids. Because of this, it is broken down more quickly by the body. The sudden increase in glutamic acid can raise the glutamate level in the blood to 20 times the usual amount.

The Ugly Truth

Research shows that MSG acts as a drug, inducing nerve-cell discharges to create a heightened taste sensation. For this reason, it has been classified as an excitatory neurotoxin (excitotoxin, for short), similar to aspartame (Nutrasweet). Therefore, many people who act negatively to MSG also cannot tolerate aspartame.

MSG can have both short- and long-term health effects, ranging from mild to life-threatening. These symptoms can occur immediately after ingesting MSG or up to 48 hours later. An individual's reaction may vary greatly from incident to incident, though the reaction time usually remains the same. Dose plays a big role in determining the reaction's severity. Also, alcohol and exercise before or immediately after exposure to MSG can increase one's sensitivity. As time goes on, an increase in the frequency and severity of MSG reactions is common.

MSG in Hiding

MSG is often combined with other substances and renamed. If you suspect that you are sensitive to MSG, print out this list, take it with you to the grocery store and check the labels of every food you buy.

These ALWAYS contain MSG These very OFTEN contain MSG

These ALWAYS contain MSG

Autolyzed yeast

Calcium caseinate



Glutamic acid

Hydrolyzed protein

Monopotassium glutamate

Monosodium glutamate

Sodium caseinate

Textured protein

Yeast extract

Yeast food

Yeast Nutrient

These very OFTEN contain MSG

Barley Malt

Calcium caseinate Bouillon

Gelatin Broth

Glutamate Carrageenan

Glutamic acid Enzyme-modified substances

Hydrolyzed protein Flavoring

Monopotassium glutamate Flavors

Monosodium glutamate Malt Extract

Sodium caseinate Malt flavoring

Textured protein Maltodextrin

Yeast extract Natural flavor/flavorings

Yeast food Natural pork/beef/chicken flavoring

Yeast Nutrient Pectin

Protein-fortified substances


Soy protein

Soy protein isolate or concentrate

Soy sauce

Soy sauce extract


Vegetable gum

Whey protein

Whey protein isolate or concentrate