Is MSG A Neurotoxin? Fact Vs. Myth


Monosodium glutamate (MSG) is the sodium salt of glutamate, the most common naturally occurring amino acid. It is used as a food additive, and confers the protein-like flavor (amino acids are the building blocks of proteins) called umami to foods when used in the proper proportions.

Since the 1970s the use of MSG to flavor foods has been controversial. Many people report symptoms of what came to be known as “Chinese Restaurant Syndrome,” which can include headache, flushing, numbness, and weakness.

While MSG is typically blamed for these complaints, the high concentrations of salt, sugar, and gluten typical in American Chinese restaurants should also be suspect. Indeed, even after several double-blind placebo controlled studies, scientists have failed to establish any link between MSG consumption and the symptoms described.

While certain people may be sensitive to MSG ingestion, most experts consider the condition to be rare and some even question its existence.

It has also been suggested that MSG can lead to acute neurotoxicity. These fears arose from a study showing that neonatal mice that were injected with or force fed very high doses of MSG suffered from brain lesions. While this may sound alarming, the same toxicity did not occur when the MSG was administered with food, even at high doses.

That the toxicity does not occur in the presence of food should be reassuring, but evidence shows that the danger is even less significant for humans. Mice are particularly sensitive to MSG, and even much higher doses of orally ingested MSG are safe for human adults and babies.

Probably the biggest concern for ingesting substantial amounts of MSG is that it increases palatability (that’s the scientific term for tastiness) of foods and can encourage overeating. However this effect may actually be beneficial in patient groups who have trouble getting sufficient nutrition, such as cancer patients and the elderly.

To summarize, while foods that contain high doses of MSG are rarely healthy, MSG itself does not contribute to health problems.

When it comes to the science of wellness, distinguishing the facts from the urban legends can be tough. That’s why we’ve enlisted Darya Pino – a scientist, foodie, and self-proclaimed geek girl. Check out the ZocDoc Blog every Tuesday to see her bust the biggest myths in health.

Image: Best Dumplings in the World, a Creative Commons Attribution (2.0) image from Stewart’s photostream.

  • waragainstlibs

    scientists believe that primates are susceptible to excitotoxic damage[26] and that humans concentrate excitotoxins in the blood more than other animals.[27]
    Based on these findings, they claim that humans are approximately 5-6
    times more susceptible to the effects of excitotoxins than rodents are.[28]
    While they agree that typical use of monosodium glutamate does not
    spike glutamic acid to extremely high levels in adults, they are
    particularly concerned with potential effects in infants and young
    children[29] and the potential long-term neurodegenerative effects of small-to-moderate spikes on plasma excitotoxin levels.[30]

  • LaLaLu

    This is such garbage. I have a husband who gets migraines from MSG and a son who gets seizures. Documented, specific to this neurotoxin.

    • googoodolls

      So your husband and your son have actually been given a placebo and MSG in the same situations and the migraine and seizure only occur in the case when they have MSG. And how many times has this test been done. If this is documented please send me the link to this peer reviewed study.

      • Kim Kremer

        It’s a pity so few people understand the difference between anecdotal evidence and empirical evidence.

        • Mary Anne Schiavone Daly

          I have MSG sleeplessness and headaches. I am not stupid and I never know when eating at a restaruant when I will be able to sleep that night. Take this as the fact of one person; I’m am only one data point, and do not require a double blind test to have experienced MSG issue for 25 years. It’s time to stop with the sophistry. The MSG thing is starting to sound like the cigarette alibis in 1965. That took 50 years for there to be enough “science” to match the common sense experience of normal people. If the stuff was safe – didn’t do something bad for so many people – there wouldn’t be 50 years of complaints about MSG.

        • DiaconRadish

          Yeah msg has been in the Asian diet almost 100 years in (since 1909) yet they are the epitome of a healthy society…. Hmmm and these “reliable” anecdote comes from Americans who experienced these symptoms from Chinese restaurants that are extremely more unhealthy than the cuisine from the country it’s trying to imitate??? Riiiiggghhhttt….

        • Jorge Gonzalez

          Try sticking dairies everywhere in restaurants in China. It so happens that roughly 50% of ethnic-Chinese people have an intolerance to dairy, or at least the kind produced by cows, which probably also accounts for the odd absence of cows or dairy in general in traditional Chinese food despite those being common among civilizations everywhere else except the Americas (where cows did not exist anyway). You could stick your cows’ milk in Chinese people’s diets, and then they would complain everywhere about an epidemic of food intolerance issues tied to dairy despite those being very unusual among caucasians. I myself have had problems with MSG consistently causing me headaches and a severe mental fog, which are extremely rare for me, and then found out that this is a publicly known problem with MSG *after* having myself established a link through personal experience and checking to see if it is a common problem. Yes, different demographics do have different susceptibilities. It doesn’t matter if it is a very rare problem for East Asian people. We are mostly not Asian here. And this debate is indeed going like the debate over cigarrettes and cancer. You should know “scientific” studies are not perfect in their way of flushing out correlations due to issues of how causation mechanisms work, among other things, and are very often also rigged because they are sponsored by people with a vested interest in getting a particular outcome to advertise just like in the case of tobacco and cancer studies.

        • Kim Kremer

          I am not calling you stupid. What happens to you is real and I would never tell you it didn’t happen. But that’s anecdotal evidence, not empirical evidence.
          When I take muscle relaxants, I get weird, psychotropic side effects that are not listed as potential side effects – not even in the “vanishingly rare” side effects. That does not mean I do not experience them.

        • cmclnd

          It’s a pity so many people are so quick to completely discount all anecdotal evidence as garbage.

        • Kim Kremer

          I don’t think people consider anecdotal evidence as ” garbage.” Anecdotal evidence frequently leads to scientific study, which produces empirical evidence.

      • WutDixLibsR

        Why would you need to do all that? MSG gives me severe pain in the neck where the spinal cord meats the brain stem, and it completely cripples me.

        You don’t need to do a placebo test, I spent 3 years studying this, noticing that the headaches only happen when eating MSG, that’s it. As I got older, it was happening more and more, it was up to once or twice a week and they were starting to last over a day. 3 years ago I spent 5 days incapacitated from this pain, couldn’t eat, couldn’t sleep, just sat on the couch with my elbows on my knees and head in my hands, falling asleep on and off.

        Over a 4 month period I had neck x-rays, an MRI and blood tests, all showed nothing. I’m sure now though, that if I had the tests done while the headache was present, it would have may shown something, like maybe the blood test could have shown the MSG. I went to physical therapy and a chiropractor but neither helped. I was prescribed muscle relaxers because my doctor thought maybe my neck muscles were causing this, but it wasn’t in the muscles, it was in the bone, in my spine.

        My wife noticed a pattern, even though I would sometimes have them on any day of the week, sometimes Monday, maybe Tues… More or less sporadic, I always had one Friday night, just after eating at either a Chinese buffet or Golden Corral. So the next week when I was at Golden Corral, I asked the manager if they put MSG in some of the foods there, and he said everything in their menu is loaded with it except the salad and deserts. He said that’s common with all restaurants.

        So, I didn’t go out to eat for the next 3 months. In fact, all I ate for that time was a raw vegan diet, and all that time, no headaches, felt great, I was getting them twice a week before, some lasting for days. So I figured out what the doctors couldn’t, it was diet related.

        I started eating normal after that 3 months, and as soon as I would get one of these headaches, I would look back at what I ate, and sure enough, MSG. I don’t know what made me suspect MSG, it never bothered me before I turned 40, that is when these neck aches started. they weren’t that bad through my 40’s, but around 48 they started getting painful, and when I turned 50, they were incapacitating.

        I’ve been doing this test for 3 years now, I think that’s a good enough test.

        As I said, the pain is where the spinal cord meats the brain stem, back of the neck, and it feels like it’s inside the bone. When I would be in pain, my urge was to have the doctor put a syringe of pain killer between my vertebrae on the neck and shoot some pain killer right inside there.

        Now I know, it’s nerve pain, caused by a neurotoxin, every time I eat MSG… Simple enough to figure out… The worst part is that nothing cures it, apirin, motrin, tylenol, none or these would relieve the pain even a little.