Does MSG Cause Migraines?
Migraines and MSG
For the past 20 years I've suffered from migraines. Initially, they occurred only once or twice a year. Then, their frequency increased to once every several months. By this time last year, I was having migraines once every 2-3 weeks.
After speaking to my physician and having my eyesight checked, I was given the recommendation that I buy a prescription for Sumatriptan succinate, a well-known migraine medication which constricts blood vessels in the brain. While I found the medicine to work quite well for me, I wasn't happy with the fact that I now depended on this drug. I decided to root out the true cause of my migraines.
My first "break" came late last year; after eating almost nothing all day, I bought a jar of peanuts and ate a good portion of its contents. Within 30 minutes, I was experiencing a migraine. I checked the contents of my peanut jar and found one unexpected ingredient: MSG.
About a month later, I went out for Thai food with some friends and immediately developed a migraine afterwards. My friends thought this was a strange development because the restaurant even advertised how it added no MSG to its food. I was stumped and just assumed my migraines were not caused by MSG.
Then, after eating some sushi, I again developed a migraine. Two days later, after buying some sashimi and dipping it into Ponzu sauce (i.e., soy sauce mixed with lime juice), I developed a second, though much milder, migraine. Clearly, soy sauce was not made with MSG. What was going on?
What Does MSG Do?
To know why MSG is often blamed for migraines, you must first know what it is. MSG is the sodium salt of glutamate. Glutamate itself, which is the flavor enhancing component of MSG, is actually an amino acid. Amino acids are the building blocks of proteins, with many being essential (i.e., not produced by the body) to life. Proteins typically contain glutamate as one of their amino acids; meats, some vegetables, and many fruits contain glutamate.
Glutamate, which is also known by its acidic name glutamic acid, is also a neurotransmitter. At least 50% of the body's nervous system relies upon glutamate to conduct messages from one nerve cell to another by acting upon its glutamate receptors. Without glutamate, memory and learning would not occur. Critical endocrine organs like the pancreas also contain glutamate receptors, and these receptors regulate the release of hormones such as insulin. Finally, and most importantly for the food industry, there are glutamate receptors on the tongue that impart a savory taste (called umami) when activated by glutamate.
The normal level of glutamate in the body is only between 8-12 micromolar (uM). When a rapid influx of glutamate occurs, such as through the eating MSG-laden food, nerve cells in the brain and spine start firing rapidly due to overstimulation of their glutamate receptors. Such overstimulation often leads to nerve cell death through a process known as excitotoxicity; in essence, the nerve cell is literally excited to death. Glutamate receptors in the pancreas are also activated, leading to an increased release of insulin. Repeated overstimulation of pancreatic cells can result in insulin overproduction, heightened hunger, as well as eventual insulin resistance by neighboring cells.
What does the FDA say about MSG?
MSG, which stands for monosodium glutamate, is often blamed for migraines, brain lesions, seizures, muscle aches, allergic responses and even death. The FDA has not said much against the use of MSG in food even though, according to its report on the substance, "data showing neuropathological lesions in neonatal animals resulting from subcutaneous or forced oral dosing of MSG has thus far been confirmed only in rodents." Also, "...ingestion of MSG solutions has been demostrated to cause transient clinical symptoms resembling those of "Chinese Restaurant Syndrome" and there is evidence that some individuals may respond to relatively small doses."
Chinese Restaurant Syndrome is a generalized malaise that consists of one or more of the following physical symptoms: chest pain, flushing, headache, sweating, burning or numbness around the mouth, throat/facial swelling and rapid heart rate. While most people suffering from this syndrome do eventually recover, there are a few that need to be hospitalized due to life-threatening conditions. The National Institutes of Health provides a detailed description of Chinese Restaurant Syndrome and how it can turn deadly.
Several recreational drugs, such as PCP and cocaine, can also cause the following described symptoms in some, but not all, persons who smoke or ingest them. However, unlike MSG, PCP and cocaine are illegal substances. Intriguingly, at one point in time cocaine was also added to food in order to enhance its taste. Carbonated beverages such as Coca-Cola proudly advertised the health benefits of special additives like cocaine. Despite these similarities between recreational drugs and MSG, however, the FDA does not overtly state that MSG intake can be dangerous to one's health. When invited to committee meetings on issues of MSG safety, the FDA is strangely unable to attend or engaged in prior commitments.
MSG and Free Glutamate are Excitotoxins!
Nerve cells rely on neurotransmitters to communicate with each other. The exchange point of the communication occurs at the receptor of the cell in a kind of "lock-and-key" fashion; in essence, the neurotransmitter "key" unlocks the receptor "lock" and thus relays a message to the neighboring nerve cell. When a message relay is about to occur, the nerve cell delivering the message is said to be "excited". An electrical impulse actually travels down its body and towards the location of the receiving receptor-containing cell. At that point, the excited nerve cell releases its neurotransmitter to the eneighboring cell. This neighboring cell, assuming it has the correct receptor (i.e., lock), will accept the neurotransmitter (i.e., key) and become excited in itself. The signal cascade continues until a nerve cell is reached that initiates the desired action (e.g., hormone release). In this way, the nervous system communicates with itself and with the body's organs and muscles.
Nerve impulses are carefully controlled and occur only when necessary. However, they can be skewed tremendously, such as when you are under the influence of a recreational drug. The recreational drug in this instance mimics a particular neurotransmitter, acting on the same nerve cell receptors that the neurotransmitter would act upon. Because there is a tremendous amount of drug present in comparison to the regular levels of the neurotransmitter, your brain, nervous system and organs feel different. You might start hallucinating or experiencing a rapid heart beat. You could experience extreme emotions. Finally, you could even die from seizure, shock, stroke or cardiac ischemia (i.e., heart attack).
In the case of glutamate, the compound acts much like a recreational drug. The symptoms of Chinese Restaurant Syndrome, which is a general malaise that MSG has become associated with, are highly suggestive of a drug-induced experience. These symptoms are primarily occurring because glutamate is inducing the repeated excitation of nerve cells. Such repeated excitation is dangerous to the cells, causing damage to quickly accrue within their bodies and on their membranes. Given enough repeated excitation, the nerve cells experience excitotoxicity and actually die. Thus, MSG and its derivative glutamate compounds are excitotoxins.
But if MSG is an Amino Acid, it's Natural, Right?
Glutamate is indeed an amino acid and therefore natural. Likewise, poisonous mushrooms are also natural. Glutamate is a non-essential amino acid produced by the body and therefore needs no external supplementation. However, beef, fish, pork, tomatoes and seaweed do contain glutamate as well as other amino acids. They can be eaten as-is and without worry about their inherent glutamate because this glutamate is not in free-form; i.e., it needs to undergo a long and convoluted process of digestion and chemical breakdown before becoming freed. Thus, glutamate that is derived from regular food sources takes quite some time to enter the bloodstream. There is no "spike" of glutamate when you eat a steak or a whole tomato; conversely, when you ingest soy sauce, a known source of free glutamate, your body is immediately bombarded by loads of glutamate. This glutamate enters your blood stream, quickly goes to your glutamate receptors, and starts acting on those receptors en masse. The results are excitotoxicity and neuronal death. Remember, glutamate is an excitotoxin.
The Scientific Research on MSG Tells a Scary Story
Scientists have successfully implicated MSG and free glutamate as direct causes of conditions such as brain lesions, obesity, learning and behavioral deficits, high cholesterol, diabetes, and reproductive dysfunction.
Regarding brain lesions and obesity:
In 1957, Drs. Lucas and Newhouse injected MSG into the retina of newborn mice and found out that it destroyed the nerve cells in their eyes. In 1969, Dr. John Olney published a paper in Science that reported how newborn laboratory animals exposed to MSG via injection developed lesions and necrosis (i.e., cell death) in specific regions of the brain, especially the hypothalamus, a brain structure noted to be high in glutamate receptors and also responsible for memory. This seminal paper is listed below:
Brain lesions, obesity, and other disturbances in mice treated with monosodium glutamate Olney JW. Science. 1969 May 9;164(880):719-21
Later on in life, these animals experienced stunted growth, suffered from morbid obesity, and had reproductive issues. Apparently, by destroying sections of the hypothalamus, MSG had also affected the endocrine functions of these animals, which are under the control of the hypothalamus (via the pituitary gland).
Because MSG could be used so readily to create obesity in mice and rats, researchers would administer MSG to laboratory mice in order to create strains of obese mice. The procedure is described in the following paper from 1976:
The induction of obesity in rodents by means of monosodium glutamate
Bunyan J, Murrell EA, Shah PP., Br J Nutr. 1976 Jan;35(1):25-39
In 2008, a study conducted in rural China found that those who prepared their food with MSG were three times as likely to be obese. These data were consistent with earlier data gathered from animal studies on MSG.
Regarding learning and behavioral deficits:
The following study, described in the paper listed below, details how pregnant rats exposed to MSG in their drinking water gave birth to offspring rats that were not only obese and "lazy", but also had trouble discriminating between positive and negative stimuli in learning exercises:
Prenatal monosodium glutamate (MSG) treatment given through the mother's diet causes behavioral deficits in rat offspring Frieder B. Grimm VE., Int J Neurosci. 1984 Apr;23(2):117-26
Young rats exposed to MSG exhibited the strange behavior of self-mutilation by chewing on their own tails:
Neonatal exposure to monosodium glutamate alters the neurobehavioral performance of adult rats Squibb RE, Tilson HA, Meyer OA, Lamartiniere CA. Neurotoxicology. 1981 Nov;2(3):471-84
Regarding high cholesterol:
Feeding adult mice a diet rich in MSG led to their increased cholesterol levels and significantly higher lipid, phospholipid, free fatty acid and triglyceride profiles:
Effects of monosodium glutamate (MSG) on serum lipids, blood glucose and cholesterol in adult male mice Ahluwalia P, Malik VB.Toxicol Lett. 1989 Feb;45(2-3):195-8
Studies on effect of monosodium glutamate (MSG) on various fractions of lipids and certain carbohydrate metabolic enzymes in liver and blood of adult male mice.
Malik VB, Ahluwalia P. Toxicol Lett.1994 Oct;74(1):69-77.
Mice with a genetic predisposition to diabetes that were fed MSG developed hyperglycemia and/or hyperinsulinemia (high blood sugar and/or high insulin levels). The MSG-fed mice also showed impaired glucose tolerance:
Effects of monosodium glutamate administration in the neonatal period on the diabetic syndrome in KK mice Cameron DP, Poon TK, Smith GC. iabetologia. 1976 Dec;12(6):621-6.
A study performed on human volunteers showed that MSG raises blood insulin levels:
Glutamate ingestion: the plasma and muscle free amino acid pools of resting humans T. E. Graham, V. Sgro, D. Friars and M. J. Gibala Am J Physiol Endocrinol Metabol. 278:E83-E89, 2000.
Regarding reproductive dysfunction:
Female rats that received MSG throughout their lifetimes were found to have smaller ovaries and uteri and lower estradiol levels compared to non-MSG treated female rats. Many more immature follicles were located in the ovaries of the rats treated with MSG. The MSG-treated rats were also shorter and obese.
Long-term effect of neonatal monosodium glutamate (MSG) treatment on reproductive system of the female rat Mi[kowiak B, Kesa B, Limanowski A, Partyka M, Filipiak B., Folia Morphol (Warsz). 1999;58(2):105-13.
Male rats given MSG throughout their lifetimes fared no better reproductively: they also had smaller pituitary glands and testes, and their blood levels of testosterone were lower. These male rats were shorter and obese compared to their no-MSG cohorts:
Effect of perinatal administration of monosodium glutamate (MSG) on the reproductive system of the male rat Mi[kowiak B, Limanowski A, Partyka M .Endokrynol Pol. 1993;44(4):497-505.
MSG injection vs ingestion
It may be argued by some folks that, in many of the research cases presented above, MSG was injected into lab animals and not ingested, as would normally be expected for most human MSG exposure. However, what many people do not realize is that certain vaccines contain MSG as one of their "inert" components. The fact that MSG is injected into humans, and specifically young children (who are four times more sensitive to the damaging effects of MSG), makes the research findings posted above even more relevant than previously thought.
Should We Just Eat MSG-Free Food?
Yes, and no. While MSG is the single biggest contributor of free glutamate, it isn't the only one. Free glutamate is everywhere and is becoming more prevalent as food manufacturers apply "clean labels" to their flavor enhancers in an attempt to avoid using the dreaded MSG word. Some major contributors of free glutamate go under the names of hydrolyzed/autolyzed protein, yeast extract, natural flavor/s, spices, textured protein, whey protein isolate, gelatin, natrium glutamate (playing on the Latin word for sodium), disodium guanylate or inosinate and just plain old glutamate or glutamic acid. A full list of all the possible disguises of free-form glutamate are provided through the Truth in Labeling Council.
Many fermented foodstuffs like soy sauce contains lots of glutamate as a by-product of their production. Tomatoes, which are naturally high in glutamate, can easily be made to release their glutamate stores via simple processes such as being pureed or cooked. In essence, the processing of protein to release its base amino acids typically results in free glutamate.
Other and lesser-known protein processing techniques include hydrolyzing, which involves degrading the protein source in a hydrochloric acid bath and then neutralizing it with sodium hydroxide. This dissolves the protein into its building blocks, the amino acids. This amino acid mixture, now termed hydrolyzed or autolyzed protein, is added to food as a flavor enhancer and consists of up to 20% free glutamate. Because it is not technically a sodium salt of only glutamate, it escapes having the MSG label applied to it.
What I Did About My Migraines
Today, almost every fast food and restaurant chain uses MSG and/or glutamate to enhance the flavor of its food. The MSG or glutamate can go under a plethora of "clean-label" names such as hydrolyzed protein, yeast extract, etc. But don't be fooled; this is the same devil in a different guise. Likewise, many fat-free and low calorie foods also contain some form of glutamate in order to enhance their otherwise lackluster flavor. It is nearly impossible to not encounter MSG and/or glutamate in away-from-home cooking, even at restaurants that label their food as "MSG-free".
Rather than despair that I would never be able to eat out again, I gathered a list of the biggest MSG and glutamate offenders. Searching online, I found a plethora of resources, such as MSGTruth.org, that listed which restaurants use MSG and free glutamate and what food items contain these excitotoxins. I learned to either avoid these food items altogether or to at least avoid their accompanying "sauces" (e.g., ranch dressing).
On the home front, I became a more discriminating food shopper. I now read ingredient labels at least three times before putting a food item in my cart. I hang out more at farmer's markets and health foods stores. And I have taken to writing food manufacturers directly when I am not sure what they mean by a specific ingredient like "natural flavors". In fact, I am currently corresponding with Naked Juice on this very subject.
As a result of my vigilence, my migraines have greatly diminished in frequency and intensity. It's actually been quite some time now since I've had to pop a Sumatriptan and I'd like to keep it that way. Of course, a food item may come along that I've not fully checked and I could develop a migraine from eating it. Still, I'm encouraged that I've finally found the real reason behind my migraines as well as a way to get rid of these headaches.