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- Meet the Writer
- Is MSG Really Bad for Your Health?
- Ask Keri: I’ve heard MSG is actually natural but also that it’s bad for the brain. Should I avoid it?
- MSG and Your Health
- The Bottom Line
- I’ll Never See Food the Same Way After Living On MSG For a Week
- Monosodium Glutamate 101: How to Use MSG in Cooking
- World-class chefs use MSG (monosodium glutamate) in their cooking, and perhaps you’re toying with the idea of giving it a try at home.
- The Truth About MSG — Is It Dangerous or Not?
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Order from any number of Chinese takeout restaurants these days, and you might notice that many menus boast “NO ADDED MSG.” The label can also be found in supermarket aisles on snack foods or on packaged seasonings.
The labels are meant to ease consumers’ worries, because MSG, which is used as a flavor enhancer, has for decades been popularly linked to various health problems, such as headaches and allergic reactions. It’s even been considered a factor in infantile obesity.
“I see people all the time who are absolutely convinced that their allergic reactions are caused by MSG—it causes this, it causes that,” says allergist and immunologist Katharine Woessner of the Scripps Clinic Medical Group, who conducted a study on MSG’s effects. But, she says, “I think there’s a great misunderstanding.”
Indeed, most scientists today agree that the notion that MSG causes sickness in humans is unfounded.
“It’s ridiculous,” says Ken Lee, a professor and the director of food innovation at The Ohio State University. “It’s wacko, it’s weird; it’s not true that MSG has any kind of toxic or causative role in food allergies.”
Lee breaks down his reasoning: “MSG stands for monosodium glutamate. So sodium—everybody knows what that is— the first ingredient in common table salt.” (Natural salt found in foods accounts for about 10 percent of a person’s total daily intake, according to the Food and Drug Administration.) Meanwhile, glutamate, the basic component of MSG, “is a synonym for glutamic acid is a naturally occurring amino acid. It’s one of the building blocks of protein,” says Lee. In aqueous solutions, MSG breaks down to sodium and glutamate.
Most living things on earth contain glutamate, says Lee, and it’s also in many foods, including tomatoes, walnuts, pecans, Parmesan cheese, peas, mushrooms, and soy sauce. An average adult consumes about 13 grams of glutamate each day from the protein in food, according to the FDA; added MSG contributes another 0.55 grams.
“It’s wacko, it’s weird; it’s not true that MSG has any kind of toxic or causative role in food allergies.”
Monosodium glutamate was discovered more than 100 years ago by a Japanese chemist named Kikunae Ikeda, who derived it from seaweed and discovered that it had unique flavor-enhancing properties. These days, MSG is made by fermenting starch, sugar beets, sugar cane, or molasses, according to the FDA.
The additive’s negative reputation can be traced back to the 1960s, when The New England Journal of Medicine published a letter from a Maryland doctor named Robert Ho Man Kwok. Kwok wrote that he experienced symptoms similar to those of an allergic reaction every time he ate food from a Chinese restaurant, and he questioned the cause. Was it the wine he was drinking, the spices in the food, or the MSG? Kwok’s letter—which referred to the collection of symptoms as “Chinese Restaurant Syndrome,” or CRS—prompted people to write in to the journal with their own experiences feeling flushed or getting headaches after consuming Chinese food, according to Lee.
On the heels of Kwok’s letter, a neuroscientist named John Olney published a study on MSG in Science. In his experiment, he injected the additive directly into white laboratory mice and found that the tests caused a number of neurological problems in his subjects, including brain lesions or impaired development. Taken together, Kwok’s letter and Olney’s study implicated MSG as the likely culprit behind CRS.
But there are problems relating Olney’s experiments to human subjects. He chose to inject mice with MSG under their skin, whereas the only way humans consume MSG is by eating it, says John Fernstrom, a professor of psychiatry, pharmacology, and chemical biology at the University of Pittsburgh School of Medicine, and glutamate is largely metabolized in the gut. “You have to read between the lines very carefully to see when there is MSG-induced brain damage,” says Fenstrom, “It’s always by injection.”
Furthermore, Olney injected the MSG into his mouse subjects in doses that were actually fit for horses—far higher than what any human would ever consume. “Anything consumed in excess is no good,” says Lee. “Everything consumed in excess could be toxic, including MSG. However, that being said, I have yet to see any documented account of somebody killing by consuming vast quantities of MSG. It would be extremely difficult to do.”
Subsequent experiments have helped dismantle the MSG-is-bad-for-you theory. For instance, in one study from 1993, researchers tested 71 subjects for reactions to MSG in relation to CRS, concluding that “rigorous and realistic scientific evidence linking the syndrome to MSG could not be found.”
In 1999, Katherine Woessner’s team conducted a single-blind, placebo-controlled study to test the effects of MSG on 100 asthmatic patients (an earlier paper suggested that asthmatics with a sensitivity to aspirin might be sensitive to MSG). The researchers found that, while 30 participants believed they had a history of CRS, only one showed signs of reduced lung function after exposure to MSG. When that subject was tested again—this time in a double-blind, placebo-controlled challenge—the test came out negative.
What’s important to keep in mind is, ‘Yes, you had that meal, yes you had those symptoms—but they’re not necessarily cause and effect.’
Then in 2000, researchers conducted the largest double-blind, placebo-controlled study on MSG, consisting of 130 subjects who said they were sensitive to the additive. The researchers found that MSG produced short-lasting and minor reactions in a subset of people—but these could not be reproduced consistently upon retesting. (Read about more MSG-related experiments in this peer-reviewed essay appearing in Clinical Correlations: The NYU Langone Online Journal of Medicine.)
Meanwhile, the FDA calls MSG “generally recognized as safe” (a classification that the agency originally made in 1959). On its website, the agency writes, “Although many people identify themselves as sensitive to MSG, in studies with such individuals given MSG or a placebo, scientists have not been able to consistently trigger reactions.”
So what about Chinese food? “If you think you get a reaction to Chinese food, maybe you do—it’s just not the MSG,” says Fernstrom, who is also a scientific advisor to the International Glutamate Technical Committee, which funds MSG research. “The thing is, there are all kinds of spices in Chinese food that are obviously plant-based—and people get allergic reactions to plants.”
Adds Woessner: “As humans, we like to have an explanation for things, and we have to eat every day,” so if you aren’t feeling well, she says, it’s normal to trace your steps back to the last meal you ate. But what’s important to keep in mind is, “Yes, you had that meal, yes you had those symptoms—but they’re not necessarily cause and effect.”
Meet the Writer
About Chau Tu
Chau Tu is an associate editor at Slate Plus. She was formerly Science Friday’s story producer/reporter.
Is MSG Really Bad for Your Health?
Ask Keri: I’ve heard MSG is actually natural but also that it’s bad for the brain. Should I avoid it?
Keri Says: MSG is an ingredient that causes lots of people to freak out. The good news: It’s not nearly as scary as its reputation. Still, you might want to avoid it if you’re sensitive to its effects.
First, what is it? MSG stands for monosodium glutamate, and it’s a food additive used to add umami flavor. Glutamate is a non-essential amino acid (which means your body makes it on its own) that’s found in foods like meat, fish, and mushrooms, and sodium is what it sounds like: salt.
RELATED: The Need-to-Know Facts on Salt in Food
Originally, MSG was made by extracting glutamate from seaweed and combining it with salt, but today it’s produced by fermenting starch, sugar cane, and molasses.
MSG and Your Health
Rumblings about MSG started to occur decades ago when rumors spread that people were experiencing symptoms like headaches, muscle tightness, numbness, and weakness after eating American Chinese food. Scientists speculated that MSG in the food could be causing excessive glutamate build-up in the brain, thereby affecting nerve cells.
Some studies were published soon after that that showed harmful neurological effects in mice, but the results have since been called into question. First of all, researchers used excessive amounts when injecting the mice, and follow-up studies on humans have shown MSG generally cannot get into the brain.
RELATED: The Gut-Brain Connection and How It Impacts Your Health
Some research has shown that a subset of the population may be more sensitive to MSG and can experience symptoms like headaches, numbness, and drowsiness after eating it. However, it has typically been shown in people who consume three or more grams of MSG without food (in water), while a serving of food with MSG typically contains less than .5 grams.
The Bottom Line
In very small amounts, all signs point to MSG being basically harmless. However, if you do feel like you’re sensitive to it and don’t feel great when you eat foods that contain it, you should totally skip it.
Here’s the biggest takeaway: Where are you going to get MSG in your diet? In addition to it famously being in Chinese takeout, it’s commonly found in processed, packaged foods like potato chips, frozen dinners, and cold cuts, and in fast food meals like chicken nuggets. I don’t want you eating that crap for a million other reasons. So, if you’re eating a healthy, whole foods diet to begin with, you’re naturally going to be avoiding MSG in most cases.
This is the professor’s ‘Eureka!’ moment. Mrs Ikeda’s kombu is to lead him to a discovery that will make his fortune and change the nature of 20th-century food. In time, it would bring about the world’s longest-lasting food scare, and as a result, kick-start the age of the rebel consumer. It was an important piece of seaweed.
Professor Ikeda was one of many scientists at the turn of the century working on the biochemical mechanics which inform our perception of the world. By 1901 they had drawn a map of the tongue, showing, crudely, the whereabouts of the different nerve endings that identify the four accepted primary tastes, sweet, sour, bitter and salty.
But Ikeda thought this matrix missed something. ‘There is,’ he said, ‘a taste which is common to asparagus, tomatoes, cheese and meat but which is not one of the four well-known tastes.’ He decided to call the fifth taste ‘umami’ – a common Japanese word that is usually translated as ‘savoury’ – or, with more magic, as ‘deliciousness’. By isolating umami, Ikeda – who had picked up some liberal notions while studying in Germany – hoped he might be able to improve the standard of living of Japan’s rural poor. And so he and his researchers began their quest to isolate deliciousness.
By 1909 the work on kombu was complete. Ikeda made his great announcement in the august pages of the Journal of the Chemical Society of Tokyo. He had isolated, he wrote, a chemical with the molecular formula C5H9NO4. This and the substance’s other properties were exactly the same as those of glutamic acid, an amino acid produced by the human body and present in many foodstuffs. When the protein containing glutamic acid is broken down – by cooking, fermentation or ripening – it becomes glutamate.
‘This study,’ concluded Professor Ikeda in triumph, ‘has discovered two facts: one is that the broth of seaweed contains glutamate and the other that glutamate causes the taste sensation “umami”.’
The next step was to stabilise the chemical. This was easy: mixing it with ordinary salt and water made monosodium glutamate – a white crystal soluble in water and easy to store. By the time he published his paper, the professor had, wisely, already patented MSG. He began to market it as a table condiment called Aji-no-moto (‘essence of taste’) that same year.
It was an instant success, and when Kidunae Ikeda died in 1936 he was a rich man: he remains, as every Japanese schoolchild knows, one of Japan’s 10 greatest inventors. The food chemicals giant Ajinomoto Corp, now owned by General Foods, pumps out a third of the 1.5 million tons of monosodium glutamate we eat every year – from India to Indonesia ‘Ajinomoto’ means MSG.
Ikeda’s original paper muses a little about MSG and why it should excite the taste buds so, without arriving at any convincing conclusion. Much more work has been done since. We now know that glutamate is present in almost every food stuff, and that the protein is so vital to our functioning that our own bodies produce 40 grams of it a day. Probably the most significant discovery in explaining human interest in umami is that human milk contains large amounts of glutamate (at about 10 times the levels present in cow’s milk). Babies have very basic taste buds: it’s believed that mother’s milk offers two taste enhancements – sugar (as lactose) and umami (as glutamate) in the hope that one or other will get the little blighters drinking. Which means mothers’ milk and a packet of cheese’n’onion crisps have rather more in common than you’d think.
When you next grate parmesan cheese onto some dull spaghetti, what you will have done in essence is add a shed-load of glutamate to stimulate your tongue’s umami receptors, thus sending a message to the brain which signals (as one neuro-researcher puts it) ‘Joy and happiness!’ Supper is rescued – and your system has added some protein and fats to a meal that was all carbohydrate.
Ripe cheese is full of glutamate, as are tomatoes. Parmesan, with 1200mg per 100 grams, is the substance with more free glutamate in it than any other natural foodstuff on the planet. Almost all foods have some naturally occurring glutamate in them but the ones with most are obvious: ripe tomatoes, cured meats, dried mushrooms, soy sauce, Bovril and of course Worcester sauce, nam pla (with 950mg per 100g) and the other fermented fish sauces of Asia.
Your mate, Marmite, with 1750mg per 100g, has more glutamate in it than any other manufactured product on the planet – except a jar of Gourmet Powder straight from the Ajinomoto MSG factory. On the label, Marmite calls it ‘yeast extract’. Nowhere in all their literature does the word ‘glutamate’ appear. I asked Unilever why they were so shy about their spread’s key ingredient, and their PR told me that it was because it was ‘naturally occurring … the glutamate occurs naturally in the yeast’.
As they put monosodium glutamate into production, Professor Ikeda and his commercial partners found that making stable glutamate from the traditional seaweed and salt was unnecessary. They developed a much simpler and cheaper process using fermented molasses or wheat – eventually manufacturers realised that almost any protein can be broken down to produce it.
The product took off, immediately, and within a few years Ajinomoto (which was now the company’s name) was selling MSG across Asia. The breakthrough to America came in the aftermath of World War Two. Like pizza and vermouth, MSG was a taste American soldiers brought home with them. They weren’t aware that MSG was what they’d liked in Japan – but the US Army catering staff noticed that their men enjoyed the leftover ration packs of the demobilised Japanese Army much more than they did their own, and began to ask why.
MSG arrived in America at a key moment. Mass production of processed food was booming. But canning, freezing and pre-cooking have a grave technical problem in common – loss of flavour. And MSG was a cheap and simple additive that made everything taste better. It went into tinned soups, salad dressings, processed meats, carbohydrate-based snacks, ice cream, bread, canned tuna, chewing gum, baby food and soft drinks. As the industry progressed, it was used in frozen, chilled and dehydrated ready meals. MSG is crucial in no-fat or low-fat food, where natural flavour is lost with the extraction of oils. It’s now found in cosmetics, pharmaceuticals, and dietary supplements.
Ajinomoto Corp started manufacturing in the States in 1956 and in 1962 allied itself with Kellogg’s. MSG sells in the States in supermarkets, under the brand Ac’cent. In Britain you will have to visit a Chinese supermarket for a supply of pure Gourmet Powder, but MSG plays a role – often in secret – in products on almost every shelf of the supermarket.
But MSG’s conquest of the planet hit a major bump in April 1968, when, in the New England Journal of Medicine, a Dr Ho Man Kwok wrote a chatty article, not specifically about MSG, whose knock-on effects were to panic the food industry. ‘I have experienced a strange syndrome whenever I have eaten out in a Chinese restaurant, especially one that served northern Chinese food. The syndrome, which usually begins 15 to 20 minutes after I have eaten the first dish, lasts for about two hours, without hangover effect. The most prominent symptoms are numbness at the back of the neck, gradually radiating to both arms and the back, general weakness and palpitations…’
And so was born Chinese restaurant syndrome (CRS) and a medico-academic industry dedicated to the researching and publicising of the dangers of MSG – the foreign migrant contaminating American kitchens. Shortly after Dr Ho came Dr John Olney at Washington University, who in 1969 injected and force-fed newborn mice with huge doses of up to four grams/kg bodyweight of MSG. He reported that they suffered brain lesions and claimed that the MSG found in just one bowl of tinned soup would do the same to the brain of a two-year-old.
Other scientists were testing MSG and finding no evidence of harm – in one 1970 study 11 humans ate up to 147 grams of the stuff every day for six weeks without any adverse reactions. At the University of Western Sydney the researchers concluded, tersely: ‘Chinese restaurant syndrome is an anecdote applied to a variety of postprandial illnesses; rigorous and realistic scientific evidence linking the syndrome to MSG could not be found.’
Science has still not found a convincing explanation for CRS: indeed, some researchers suggest it may well be to do with the other things diners have imbibed there – peanuts, shellfish, large amounts of lager. Others say that fear of MSG is a form of mass psychosis – you suffer the symptoms you’ve been told to worry about.
The fact is that, since the eighties, mainstream science has got bored of MSG. Some research continues; in 2002, for example, New Scientist got very excited over a report that MSG might damage your eyesight, after Japanese scientists announced that they had produced retinal thinning in baby rats fed with MSG. It turned out they were putting 20 grams of MSG in every 100g of rat food – an amazing amount, given that, in the UK, we adults consume about four grams of it each a week. (One project took people who were convinced their asthma was caused by MSG and fed them up to six grams of it a day, without ill-effects). However, at no time has any official body, governmental or academic, ever found it necessary to warn humans against consuming MSG.
But popular opinion has travelled – spectacularly – in the opposite direction to science. By the early eighties, fuelled by books like Russell Blaylock’s Excitotoxins – The Taste That Kills, MSG’s name was utter mud. Google MSG today, and you’ll find it blamed for causing asthma attacks, migraines, hypertension and heart disease, dehydration, chest pains, depression, attention deficit disorder, anaphylactic shock, Alzheimer’s and Parkinson’s diseases and a host of diverse allergies.
Thus since 1968 the processed food industry has had its own nasty headache as a result of MSG. Hundreds of processed products would have to be withdrawn if amino-acid based flavour-enhancers could not be used. They would become, simply, tasteless. By the 1980s a third of all Americans believed it was actively harmful. Crisp-buying teenagers thought MSG made them stupid and spotty. Mothers read that MSG could put holes in their children’s brains.
So the food industry employed its usual tactic in the face of consumer criticism: MSG was buried by giving it new names. The industry came up with a fabulous range of euphemisms for monosodium glutamate – the most cheeky of all is ‘natural flavourings’ (however, the industry did remove MSG from high-end baby foods).
Nowadays the industry’s PR beats a big drum. ‘Natural, Tasty, Safe’ is the slogan. ‘Many people believe that monosodium glutamate is made from chemicals. Monosodium glutamate is a chemical in the same way that the water we drink and the oxygen we breathe are chemicals,’ explains an MSG website.
MSG manufacturers are now pushing it as actively useful for health – a way to eat less salt – and they have pursued the celebrity route too. Heston Blumenthal, of the Fat Duck in Bray, is among the eminent chefs the industry has enlisted for promotion of the umami principle at conferences across the world – although he uses traditional sources like kombu.
It’s not surprising that the MSG-makers are so busy on their product’s image, because MSG-phobia still shows no signs of subsiding. This despite the fact that every concerned public body that ever investigated it has given it a clean bill of health, including the EU, the United Nations food agencies (which in 1988 put MSG on the list of ‘safest food additives’), and the British, Japanese and Australian governments.
In fact, every government across the world that has a food licensing and testing system gives MSG – ‘at normal levels in the diet’ – the thumbs-up. The US Food and Drug Administration has three times, in 1958, 1991 and 1998, reviewed the evidence, tested the chemical and pronounced it ‘genuinely recognised as safe.
However, there remains a body of respected nutritionists who are sure MSG causes problems – especially in children. And parents listen. Most doctors who offer guides to parents qualify their warnings about MSG – it may cause problems, it has been anecdotally linked with disorders. But public figures like the best-selling nutrition guru Patrick Holford are powerful advocates against MSG. He’s sure the science shows that MSG causes migraines and he is convinced of the dangers of the substance to children, particularly in the child-grabber snacks like Monster Munch and Cheesy Wotsits .
‘I’m a practitioner and there’s no doubt that kids with behavioural problems react to MSG,’ he says. ‘I’ve given them the foods, and seen the different reactions. Glutamate is a brain stimulant in the way that it is given, because it enhances sensory perception in the sense that things taste much better – and some kids become very hyperactive.’
Holford admits that he has not measured this hyperactivity, or tested MSG by itself on children – his statements are based on anecdotal comparison of the effects of plain crisps versus flavoured ones. But there is some justice in his complaint that in all the acres of research on MSG, ‘most is directed at the possible physiological effects, not the behavioural ones’.
Eric Taylor, professor of child and adolescent psychiatry at King’s College in London, is among the leading British experts on food additives and children’s behaviour. He was a pioneer of ‘elimination tests’ that examined food additives and their effect on children – establishing, for one, that the colouring tartrazine did contribute to hyperactivity.
Yet he does not think MSG is a culprit and he has never tested it. Why? ‘There are so many substances, and there’s not much funding. And, with MSG, there’s no reasonable physiological theorem to justify the research.’ The only investigation he has seen on children’s brains and MSG, conducted in the seventies, suggested that the substance might improve reading ability.
Patrick Holford, like many of MSG’s foes, also talks of its possible addictive properties and he cannot explain why ‘natural’ glutamate, say in cheese or parma ham, should be any less addictive, or harmful, than glutamate that’s been industrially produced and stabilised with salt.
The anti-additive movement (check out the excellent and informative www.truthinlabeling.org) admits that ‘natural’ and ‘industrially produced’ glutamate are chemically the same, and treated by the body similarly. So why doesn’t anyone ever complain of a headache or hyperactivity after a four cheese and tomato pizza (where there’s easily as much glutamate as in an MSG-enhanced chicken chow mein)?
Their answer is that the industrial fermentation process introduces contaminants. This is possible, of course, but it ignores the fact that whole swaths of the planet – including East Asia, where I live – do not have any problem with MSG. Here in Thailand, the phong chu rot sits on the table with the fish sauce and the chilli powder where you would have the salt and pepper.
MSG has had one unarguable effect on us – and it is a benign one. It has made consumers look at the small print. In turn this kick-started the organic food movement and other, more militant consumer power groups. 1968 was a good year for rebels, and the dawn of MSG-phobia coincides with the beginning of a great shift in middle-class consumers’ thinking – a withdrawal of our faith in the vast corporations that fed and medicated us. After 1968 we began to question them and their motives. Friends of the Earth and Greenpeace came next.
It is now 37 years since Dr Ho Man Kwok named Chinese restaurant syndrome, and it’s plain that the case against MSG remains unproven. So either you conclude, as some will, that government, science and the mega-corporates of the food industry really are all in league with each other to poison us for profit. Or, like me, you make a different decision.
Now, I have little faith in the food industry and I’m as suspicious of food additives as the next person – I spend many hours fighting the grim battle to keep them from my children’s mouths. But until new evidence emerges I am going to give MSG a conditional discharge. But would I have it in the kitchen? Well, I did. I bought a little bag of Ajinomoto from the corner shop on our Bangkok street and tried it, a gram (the tip of a teaspoon) at a time.
By itself it tasted of almost nothing. So I beat up and fried two eggs, and tried one with MSG, one without. The MSG one had more egg flavour, and didn’t need any salting. I tried the crystals on my son’s leftover pieces of chicken breast (definitely more chickeny). I tried it in a peanut butter sandwich (nothing). On Weetabix with milk (interesting, sort of malty) and on Weetabix with milk and sugar (thought I was going to be sick).
My friend Nic came round. He told me about a Japanese restaurant he’d been to that gave him headaches and a ‘weird tingling in the cheeks’ – until he told them to stop with the MSG. Then he was fine, he said. I nodded and I served him two tomato and chive salads; both were made using the very same ingredients but I told him one plate of tomatoes was ‘organic’, the other ‘factory-farmed’. The organic tomatoes were far better, we agreed. These, of course, were the tomatoes doused with mono sodium glutamate.
Then we ate mascarpone, parma ham and tomato pizza. Nic felt fine. So did I. I had ingested, I reckoned, a good six grams of MSG over the day, and probably the same again in free glutamate from the food – the equivalent of eating two 250g jars of Marmite.
I’ve thrown the Ajinomoto out now. It works, but it was embarrassing – a bit like having a packet of Bisto in the cupboard. There is no need to have MSG in the kitchen. If I want extra glutamate in my food I’ll use parmesan, or tomato purée, or soy sauce. Or like Mrs Ikeda, boil up some kelp.
So you think you don’t eat MSG? Think again…
Some of the names MSG goes under
autolyzed yeast extract
E621 (E620-625 are all glutamates)
The following may also contain MSG natural flavours or seasonings
natural beef or chicken flavouring
hydrolyzed milk or plant protein
Free glutamate content of foods (mg per 100g) roquefort cheese 1280
parmesan cheese 1200
soy sauce 1090
fresh tomato juice 260
grape juice 258
human milk 22
For more on the MSG debate visit: www.truthinlabeling.org, www.msgmyth.com, www.msgtruth.org or www.food.gov.uk.
I’ll Never See Food the Same Way After Living On MSG For a Week
I grew up in a toxin-free household. My dad worked in the health food industry and my mom was intent on making sure that we avoided our sodium lauryl sulfates and our fluorides. And yeah, sure, I understand that: Why put ‘chemicals’ (using the word ‘chemicals’ like someone who tries to keep things all-natural would use it, not in the literal way as in the basic building blocks of the universe) in your body if you don’t have to?
So as soon as I left the nest, I went hog wild on a diet of nitrates, aspartame, and tap water, revelling in that which was once forbidden, like a priest’s daughter drinking half a handle and fucking the entire lacrosse team. For me, it was the nitrate-ridden hot dogs and diarrhea-inducing aspartame gum instead of booze and dicks. But more than anything, my favorite toxin has always been MSG.
An abbreviation of the chemical name ‘makes stuff good’ (or ‘monosodium glutamate’) was invented in Japan in 1908 when a food scientist, Kikunae Ikeda, was fucking around with some seaweed and was like, “Damn this tastes good,” and then continued to do food alchemy to it until it was in its purest form: A crystalline white powder. It was so good that he named an entire taste after it. Not a flavor, an entire fucking taste, like sweet or salty. And it’s a taste you’ve probably heard of too: ‘Umami’ pretty much means ‘tastes like MSG.’ If you like umami, you like MSG. Glutamate is a naturally occurring amino acid that the body actually needs and uses, but the synthetic form that’s found in MSG produces a kind that is not found in nature—a.k.a. the freaky stuff. According to a recent study, MSG has a tendency to overstimulate cells to death (you can take ‘overstimulate cells’ to mean ‘be so tasty it explodes nuclei’) which can result in headaches, diarrhea, and fibromyalgia. Then again, there are others that claim that it’s totally harmless.
MSG is in much of the food in American supermarkets, but it’s still treated as if it’s poison by people who don’t realize just how much of it they eat every day. So I took on the task of putting it in all of my meals for a week. I was a little worried because I had never sampled this quantity in my life. I figured that acquiring such a hazardous material would be difficult, but quickly discovered it hanging out in my local supermarket. It’s very cheap, about $2.49 for a near infinite amount of servings (you’re only supposed to use ⅛ tsp for a pound of meat.)
All photos by the author.
I tried a little on it’s own: It’s gross. And that’s OK, because it’s not supposed to be good. It’s a flavor enhancer; it just brings out the flavors that are already there. I started carrying a container of it with me wherever I went like an addict, checking for ‘phone, keys, wallet, MSG,’ every time I left the house. When you offer people at the office, in bars, or at brunch “a little MSG with that,” you’ll get a confused and disgusted “no,” which can either be traced back to the unfair stigma that MSG has, or that people consider it weird if you carry a little vial of crystals around with you no matter what they are.
I whipped up a little MSG vinaigrette and a regular one; I needed a control sample because this is a totally legitimate scientific study. I drizzled both over some kale. I took a bite of the regular dressing. It was alright, but nothing special. Then I tried the MSG-laden greens. Incredible! It had an entirely different flavor profile and had a much deeper flavor to it. I devoured the whole salad. When I returned to the non-MSG salad, it tasted way worse than it had tasted before I had sampled the MSG salad. Having a little bit of MSG Parmesan vinaigrette had made me crave more, and I had an insatiable hunger for MSG, like when you eat human flesh and then crave more and more.
The same week I started my MSG challenge, I also found out that it’s very easy to make your own butter, so I made my own with a bunch of MSG in it. It was excellent, but it was also my first time attempting to make it on my own, so I can’t attest to how much better it was. I ended up throwing the powder into cocktails, take-out, and anything else that I was putting into my mouth. I enhanced a health food chip that bragged ‘no-MSG’ by sprinkling a ton of MSG in the bag, and noticed a significant uptick in its nacho ‘cheese’ flavor. A crock pot roast recipe I made called for the addition of condensed mushroom soup and powdered onion soup mix, so I made a version with real mushrooms, real onions, and a ton of MSG (what my delicious fresh vegetables were missing). The flavor of the mushrooms really stood out, and the cheap cut of meat I used was incredibly tender.
I even added some to my favorite cocktail: a version of a Gibson with a splash of pickle juice. I had to wait for the bartender to turn around because they’re usually so not cool with people pouring powdered substances into their drinks. My friends all thought it was weird at first, but after they had a sip and liked what they tasted, we were all secretly slipping MSG into our drinks for the rest of the night. I knew from experience that MSG’d beer was bad, but it didn’t stop my dumb friends from trying it.
Don’t try this at home, kids.
Throughout my week of the white powder, the only two things that were made truly terrible with MSG were a peanut butter and jelly sandwich and a yogurt parfait. It’s just not meant for sweet stuff.
During that time of experimentation, I didn’t notice any adverse health effects, I never felt the supposed ‘Chinese Food Syndrome’ other than a headache one morning, but I’d also been drinking the previous night because I’m a terrible scientist, so I don’t know if it was a booze or an MSG hangover. But only 36 hours after I went off the week-long diet, I started to feel flu-like pains, extreme fatigue, and appetite loss. I wondered, Was this MSG withdrawal? Was I not hungry because the food I had in front of me wasn’t alchemically made more delicious by that most magical white powder?
I went 18 long years without MSG, outside of the occasional snack bag of chips, I’m happy to have this mana of flavor in my life. It made me feel a little shitty after eating so much of it, but I also could have been just having a forced psychosomatic response like so many other ‘food sensitivities.’
Or maybe I just had a hangover.
Monosodium Glutamate 101: How to Use MSG in Cooking
World-class chefs use MSG (monosodium glutamate) in their cooking, and perhaps you’re toying with the idea of giving it a try at home.
Why should you go for it? Quite simply, because seasoning many foods with MSG makes them taste better!
MSG is a purified form of glutamate, the amino acid responsible for umami (savory) flavor. By using it to increase the savoriness of a dish, the dish will taste richer and meatier. The savory flavor from MSG will also balance out other flavors like sweet and sour, and cancel out the bitter flavor found naturally in many vegetables. Another perk of MSG is that it can be used to lower the amount of sodium in a food (by up to 40%!) without making the food taste bland. So it’s understandable that some chefs consider not using MSG when cooking to be akin to not using salt.
Another perk of MSG is that it can be used to lower the amount of sodium in a food (by up to 40%!) without making the food taste bland.
Once you’ve decided to try MSG in your home cooking, you may be wondering where to start. First, look for MSG in the spice aisle or the Asian foods section of your local grocery store. It comes as a granulated white powder similar in appearance to salt, and may be found under the brand names of Ajinomoto® or Ac’cent®. Once you’re home and ready to try it out, know that MSG works best in meat, poultry, fish, seafood, vegetable, and egg dishes as well as soups and gravies, as these foods inherently have some umami flavor that MSG accentuates. Add the MSG before or during cooking at the same time you would add other seasonings like salt and pepper. About ½ teaspoon of MSG is enough to season a pound of meat or a dish that serves 4 to 6 people. Like with all seasonings, personal preferences vary, so you may want to start with a smaller amount and adjust upwards to suit your taste until you’re used to cooking with it. This is particularly important as putting too much MSG in a dish will give it an off flavor. And, you’ll want to add less salt initially until you learn how using both seasonings together affects the overall flavor of a dish.
It’s essential to note that MSG is not a magic wand. It will heighten the flavor of good food, but it can’t make bad food suddenly taste delicious. But, if you’re ready to banish the bland and elevate your cooking, give MSG a shot. It can be daunting to try a new ingredient, but if you start with small amounts using the tips listed above, you can’t go wrong.
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Read more: “8 Tips for Using MSG in Cooking and in Recipes”
Tip #5: Approximately one-half teaspoon of MSG is an effective amount to enhance the flavor of a pound of meat or four-to-six servings of vegetables, casseroles or soup.
Chris Mohr, PhD, RD is a member of the Men’s Health Advisory Board.
You’ll find the phrase “NO MSG” slapped on everything from steak seasoning to chicken broth to Chinese restaurant menus.
Yet MSG, also known as monosodium glutamate, doesn’t deserve its bad reputation, which all stemmed from a 1968 opinion piece published in the New England Journal of Medicine.
In that article, the physician named R.H. Kwok, discussed feelings of weakness, heart palpitations, headaches, and pain radiating in his arms—all after frequenting Chinese restaurants. He posited that cooking wine, MSG, or salt, might be to blame. The title of the paper: “Chinese-restaurant syndrome.”
Around the same time, a published study demonstrated what happened when scientists injected neonatal mice with large doses of MSG. Those rodents that took the 25,000 mg/kg megadose experienced rapid brain deterioration.
When the mice grew to be adults, they were notably smaller in stature, obese, and had trouble reproducing. The author of that paper extrapolated this information to suggest that pregnant women should avoid MSG for fear of the same neural effects for their newborns.
So, to summarize, the findings that characterized MSG as evil were based on an opinion letter and a rodent study. And, to date, no peer-reviewed research since has duplicated these findings.
That said, four out of 10 people still actively avoid MSG according to International Food Information Council Foundation.
I’m here to tell you, as a registered dietitian, that you don’t have to avoid MSG.
If that’s not enough for you, consider that in January 2018 the International Headache Society removed MSG from its list of causative factors for headaches after studies disproved any connection.
In December 2018, John Fernstrom, Ph.D., professor of psychiatry and pharmacology at the University of Pittsburgh, published a study review on the supposed ill effects of MSG.
His team’s conclusion: “Findings from our data and other human studies provide important evidence that MSG in the food supply presents no hazard to the human brain. Oral ingestion of glutamate does not cross the blood brain barrier.”
Americans consume about 500 mg/day (or about 7 mg/kg/day for a 70 kg person). That number is higher in Asian cultures, but is nowhere near the 25,000 mg/kg (3000-5000 mg/kg) megadose of the now notorious mice study.
Don’t fear MSG, largely because MSG makes food taste good.
“Umami is a really important factor in terms of making foods taste delish—and MSG is a concentrated form of umami,” says Ellie Krieger, R.D.N., and host of Ellie’s Real Good Food. “I think one of the biggest issues with MSG is the company it keeps—meaning the foods it’s often found in. It’s not MSG itself that’s of concern, but it can make poor-quality food taste great too so they may be more appealing than they would otherwise be.”
But there’s also a governor chip of sorts that comes with monosodium glutamate. “MSG intake is self-limiting,” says Fernstrom. “A small amount gives food an amazing flavor, whereas too much tastes unpleasant, limiting the amounts you are likely to consume.”
Unless, of course you’re a lab rat.
Chris Mohr, PhD, RD Chris Mohr, PhD, RD is the co-owner of Mohr Results, Inc (MohrResults.com) a well-being consulting company
Long ago, in a land called the 1990s, our food fears were very different than they are now. Sure, we’ve been worried about MSG on some level for ages. But back in the ’90’s, it was all about avoiding fat. The low-carb craze had barely started and we still thought fat was the devil, and Snackwell’s cookies of sadness—fat-free but with plenty of sugar (because we weren’t freaking out about sugar yet, not really)—still roamed the munchies aisle. “Non-GMO” labels hadn’t been graffitied on every box of granola. And Kale was the name of a guy in my brother’s class, not the launch of a million health trends. Nowadays, we’re awash in food-specific chemophobia, largely thanks to the popularity of “clean eating,” which drives us towards GMO-, chemical-, and so-called-toxin-free foods and food products, even after information becomes available that the things we thought were dangerous are actually perfectly safe.
One food fear has persisted since the 1960s: the mortal danger caused by monosodium glutamate, also known as MSG. I remember my father requesting “no MSG” when we went out to Chinese restaurants. I was young and I don’t remember much other than hearing that it was bad for you and that Chinese food never quite tasted as good when we went out with my father.
Thanks to the internet, we have the ability to both debunk old wives’ tales and make up new ones. But no matter how many efforts are made by science writers, there is always someone who says MSG gives them headaches. Or it gives them intestinal problems. Or the MSG ate their homework. (It’s worth noting that some people may have sensitivity to MSG when ingesting it in large amounts, but the chances of something like this happening is so small that MSG sensitivity isn’t widespread—more on that below.) Despite the fact that the FDA first recognized MSG as safe in 1959—1959!—56 years later in 2015, $9.2 billion worth of food products were labeled as being MSG-free. The history of our love/fear relationship with MSG is wrought with bad science and more than a dash of xenophobia. If you want that wonderful umami flavor in your food, let’s calm your food fears and take a look at the science of the salt.
What exactly is MSG?
Let’s parse this piece by piece. Glutamate is a form of glutamic acid, an amino acid that’s naturally occurring in many common foods, like tomatoes and cheeses. In 1908, a Japanese chemist named Ikeda Kikunae noticed the distinct flavor—one not covered by the classical “four flavor grouping” of sweet, sour, salty, and bitter—in a seaweed broth called konbu. Though other chefs had identified the unique flavor before, Kikunae was the first one to chemically isolate the glutamate from the seaweed. In one of few cases when licking the specimen is advisable, Kikunae determined that it was responsible for the flavor, which he called “umami,” derived from the word Japanese word umai, roughly translating to “deliciousness.” That’s right—the person who discovered umami is the same person who created MSG. Glutamate is an ionized form of glutamic acid, and Kukunae combined it with sodium to form the crystallized product that was shelf stable, dissolved easily into food, and gave the world ready access to that wonderful umami flavor.
How did MSG fear start?
If you know someone who claims to have a negative reaction to MSG, you can thank the New England Journal of Medicine for publishing a letter from Dr. Robert Ho Man Kwok in 1968 under the title “Chinese Restaurant Syndrome” (CRS). Dr. Kwok said that he never experienced any negative symptoms after eating food in his native China, but here in the U.S., Chinese food caused him to experience an array of symptoms, including “numbness at the back of the neck, gradually radiating to both arms and the back, and general weakness and palpitation.” The NEJM was then inundated with personal accounts of similar symptoms. It’s important to note that Dr. Kwok merely suggested MSG as one of many possible causes of his symptoms, as opposed to laying the blame squarely on it, but the notion stuck. As we’ve seen time and again, when unproven hypotheses and anecdotal evidence enter the vernacular and the collective consciousness, they’re hard to vanquish.
Despite the absence of high-quality data on “Chinese Restaurant Syndrome,” MSG quickly absorbed the blame for it, and the fear of it hasn’t diminished over the years.
Why are people so convinced that we all should avoid MSG?
MSG was introduced to the United States in the 1930s; to this day, MSG is found in packaged soups, salad dressings, crackers, and chips around the world. But even though Americans were consuming MSG in the products they bought from supermarkets, the ingredient has come to be thought of as unique to Chinese restaurants. Why did we only expect it from Chinese food and not from other glutamate-containing foods? Why don’t we hear about headaches from, for example, Campbell’s soups, which, until recently, had MSG added to it? I’ve never heard of a complaint about mushrooms or pasta with parmesan cheese. Some scholars believe that Americans’ negative perceptions of China and Chinese people are at least partially responsible for MSG’s demonization. It’s a fairly common conclusion that our fears of MSG, specifically in Chinese food, were partially the result of xenophobia.
In 1908, over a bowl of seaweed soup, Japanese scientist Kikunae Ikeda asked a question that would change the food industry forever: what gave dashi, a ubiquitous Japanese soup base, its meaty flavor? In Japanese cuisine, dashi, a fermented base made from boiled seaweed and dried fish, was widely used by chefs to add extra oomph to meals–pairing well with other savory, but meatless foods like vegetables and soy. For some reason that was generally accepted but inexplicable, dashi made these meatless foods meaty–and Ikeda was determined to find out why.
Ikeda was able to isolate the main substance of dashi–the seaweed Laminaria japonica. He then took the seaweed and ran it through a series of chemical experiments, using evaporation to isolate a specific compound within the seaweed. After days of evaporating and treating the seaweed, he saw the development of a crystalline form. When he tasted the crystals, he recognized the distinct savory taste that dashi lent to other foods, a taste that he deemed umami, from the Japanese umai (delicious.) It was a breakthrough that challenged a cornerstone of culinary thinking: instead of four tastes—sweet, salty, bitter and sour—there were now five. A new frontier of taste had been discovered, and Ikeda wasted no time monopolizing on his discovery.
He determined the molecular formula of the crystals: C5H9NO4, the same as glutamic acid, an amino acid designated as non-essential because the human body, as well as a large smattering of other plants and animals is able to produce it on its own. In the body, glutamic acid is often found as glutamate, a different compound that has one less hydrogen atom. Glutamate is one of the most abundant excitatory neurotransmitters in brain, playing a crucial role in memory and learning. The FDA estimates that the average adult consumes 13 grams of it a day from the protein in food. Non-meat food sources like tomatoes and Parmesan cheese have high levels of glutamic acid.
In 1909, Ikeda began mass-producing Ajinomoto (meaning “essence of taste”), an additive that came out of his creation of the first method of industrially producing glutamate by way of fermented vegetable proteins. The resulting sodium salt form of glutamic acid (the acid with just a single sodium molecule) became famous for its ability to imbue a meaty flavor into dishes, or just naturally enhance the flavor of food. It was touted as a nutritional wonder, helping bland but nutritious food become delicious. A growing number of Japanese housewives used the product, and by the 1930s, recipes included Ajinomoto use in their directions. The sodium salt of glutamic acid remains prevalent today–anyone who has eaten KFC or Doritos has ingested it; it’s just known by a different name: monosodium glutamate, or MSG.
Panda-inspired bottles of Ajinomto’s glutamtic salt. (Photo via Flickr user Kinya Hanada)
Few letters have the power to stop conversation in its tracks more than MSG, one of the most infamous additives in the food industry. The three little letters carry so much negative weight that they’re often whispered sheepishly or, more often, decidedly preceded by the modifier “NO” that seems to make everyone breathe a collective sigh of relief when they go out to eat. Nobody wants MSG in their food—the protest goes—it causes headaches, stomachaches, dizziness and general malaise. It’s unhealthy and, maybe even worse, unsexy, used by lazy chefs as an excuse for flavor, not an enhancement.
On the other side of the spectrum lies umami: few foodie buzzwords pop off the lips with such entertaining ease. Enterprising young chefs like David Chang (of Momofuku fame) and Adam Fleischman, of the LA-based chain Umami Burger, have built their culinary careers on the basis of the fifth taste, revitalizing an interest in the meaty-depth of umami. It’s difficult to watch the Food Network or Travel Channel or any food-based program without hearing mention of the taste wunderkind, a host or chef cooing over the deep umami flavors of a Portobello mushroom. Where MSG is scary, umami is exciting.
What few people understand is that the hated MSG and the adored umami are chemically related: umami is tasted by the very receptors that MSG targets. At a MAD Symposium in Denmark, a TED-like conference for the food industry, Chang spoke about MSG and umami: “For me, the way that I’m looking at umami, it’s the same way I look at MSG. It’s one in the same.” But if chefs like Chang (neither inept nor lazy when it comes to flavor, as his Michelin stars would attest to) are down with MSG, why does the additive retain such a bad reputation?
After gaining a foothold in Japanese cooking columns, MSG spread throughout Asia, becoming especially popular in Chinese cooking for enhancing both stocks and vegetarian dishes. Everyone knows this connection, and probably associates MSG use in America most heavily with Chinese restaurants–thanks in large part to the absurdly racist name for MSG sensitivity “Chinese Restaurant Syndrome.” But MSG’s foray into American cuisine came from more than Chinese dishes; MSG became popular in the United States during World War II thanks in large part to the country’s increasing military-industrial complex. The military thought that they had found in MSG an answer to the flavorless rations allotted to soldiers, and when the war ended, the troops came home and so did the industrialization of food production. From canned vegetables to frozen dinners, industrially created food was met with wonder in the United States.
That all changed in the 1960s, when trust in industrial food began to wane. In 1962, Rachel Carson published Silent Spring, a manifesto against pesticides that kicked off the environmental movement. As pesticides quickly fell from grace, faith in the industry of yesteryear–of the chemicals and additives born from the war—declined as well. In 1968, MSG’s death knell rang in the form of a letter written to the New England Journal of Medicine by Robert Ho Man Kwok, a Chinese-American doctor from Maryland. Kwok claimed that after eating at Chinese restaurants, he often came down with certain unpleasant symptoms, namely “numbness at the back of the neck, gradually radiating to both arms and the back” and “general weakness and palpitation.” After Kwok’s letter ran, the journal received a deluge of letters from other readers, all claiming to suffer from the same affliction, deemed “Chinese Restaurant Syndrome” by editors. Some readers presented the same symptoms as Kwok, but most were extremely varied, ranging from cold sweats to extreme dizziness. In response, the Journal offered up MSG as the likely culprit for their reader’s unpleasant symptoms.
Public interest spurred a number of scientific inquiries into the potential danger of MSG. According to food historian Ian Mosby’s exploration of MSG in “That Won-Ton Soup Headache” these inquiries went one of two ways: they either sought to prove the harmful short-term effects of MSG (and Chinese Restaurant Syndrome) or they looked to identify more long-term damage caused by the additive. Initially, researchers had success proving both the short-term and long-term dangers of MSG: mice injected with the additive showed signs of brain lesions, and humans fed 3 grams of MSG per 200 ml of soup presented symptoms congruent with “Chinese Restaurant Syndrome.” Subsequent studies, however, provided mixed results: some confirmed findings of brain lesions in animals or symptoms in humans, but other studies were unable to replicate the results. Double-blind studies often showed little correlation between MSG and adverse symptoms. Parties on both sides of the debate slung accusations at the other, with the anti-MSG researchers claiming that studies were being funded by MSG producers, and pro-MSG researchers accusing the other side of fear-mongering.
From the FDA to the United Nations to various governments (Australia, Britain and Japan) the public bodies that have investigated MSG have deemed it a safe food additive. The FDA states on their website:
FDA considers the addition of MSG to foods to be “generally recognized as safe” (GRAS). Although many people identify themselves as sensitive to MSG, in studies with such individuals given MSG or a placebo, scientists have not been able to consistently trigger reactions.
Scientific interest in its deleterious effects seems to be waning: one of the last studies to gain public attention was published in 2011. The authors of that study claimed to have found a link between MSG and obesity, though those results have been questioned. While the general scientific consensus seems to be that only in large doses and on an empty stomach can MSG temporarily affect a small subset of the population, MSG’s reputation is still maligned in the public eye.
On the other hand, MSG’s glutamic cousin umami suffers no public scorn: in 2010, umami was deemed one of the most delicious food trends to watch. When Adam Fleischman’s Umami Burger (a burger chain devoted to all things umami) opened a New York outpost, the wait for a meaty bite stretched on for three-hours. In addition to piling natural glutamates onto their burger to ensure the most umami flavor, Umami Burger enhances the burger with their “umami dust,” a blend of dried mushrooms and seaweed, and umami sauce, which includes soy and Marmite. Altogether, an original Umami Burger contains 2,185 mg of glutamate.
A highly glutamic burger from Umami Burger. (Photo via Wikipedia)
“Most people don’t know the connection between umami and MSG. They know about it from the fifth taste, and the fifth taste was always called umami and not MSG,” Fleischman explains. “We didn’t feel that using MSG was creative enough. We wanted to do it ourselves. By doing it ourselves, we could create a flavor that was umami without the stigma of MSG. MSG, whether you like it or not, has been marketed so poorly, it sounds like this horrible thing.”
By harnessing natural glutamates for their burgers, Umami Burger avoids negative connotations associated with MSG. But the “natural” glutamates in an Umami Burger aren’t chemically any different from glutamtes in MSG.
“The short answer is that there is no difference: glutamate is glutamate is glutamate,” says Richard Amasino, professor of biochemistry at University of Wisconsin-Madison. “It would be identical unless different things created a different rate of uptake.”
Glutamtes that occur naturally in food come intertwined with different chemicals or fiber, which the body is naturally inclined to regulate, explains Amy Cheng Vollmer, professor of biology at Swarthmore College. MSG, however, comes without the natural components of food that help the body regulate glutamic levels. It’s like taking an iron supplement versus obtaining iron from spinach or red meat: the iron supplement creates an expressway between the iron and your bloodstream that you wouldn’t find in natural iron sources.
“The bottom line here is context is everything,” Vollmer adds.
So does MSG deserve its bad rap? For the small section of the population that shows sensitivity to it, probably. But for the rest of America, maybe it’s time to reconsider exactly what we’re so afraid of when it comes to MSG.
The Truth About MSG — Is It Dangerous or Not?
So why do people continue to condemn MSG even after 40 years of science have failed to show that eating MSG causes harm? Because once fear is ingrained, it’s difficult to completely remove.
Adding to this consumer uncertainty is the fact that the true cause of CRS is still a mystery. Many people are left wondering, “Why do some people feel ill after eating food containing MSG?” Some researchers speculate that the symptoms of CRS are caused by referred pain due to irritation of the esophagus.14 Others suspect it could involve a Vitamin B6 deficiency or the high histamine levels present in many Chinese foods.12,11,9
Read the full-length article to learn about the discovery and production of MSG.
Read the full-length article to learn about umami as the fifth taste.
Read the full-length article to learn about labeling regulations for MSG and other flavor enhancers.
Read the full-length article to learn about MSG and migraines.
Read the full-length article to learn about MSG and asthma.
Read the full-length article to learn why MSG keeps getting a bad reputation on the internet.
Read the full-length article for advice on your next step.
1. Medline Plus. Amino Acids. (2013). at //www.nlm.nih.gov/medlineplus/ency/article/002222.htm
2. Center for Food Safety and Applied Nutrition. Food Additives & Ingredients – Questions and Answers on Monosodium glutamate (MSG). at //www.fda.gov/food/ingredientspackaginglabeling/foodadditivesingredients/ucm328728.htm
3. Abegaz, E. Interview with Dr. Abegaz of Ajinomoto USA. (2014).
4. Naum, M. Interview with FDA Spokeswoman Marianna Naum, Ph.D. (2014).
6. Marcus, J. B. Unleashing the Power of Umami. Food Technology Volume 63, (2009).
7. Jinap, S. & Hajeb, P. Glutamate. Its applications in food and contribution to health. Appetite 55, 1-10 (2010).
8. Williams, A. N. & Woessner, K. M. Monosodium glutamate ‘allergy’: menace or myth? Clinical & Experimental Allergy 39, 640-646 (2009).
9. Federation of American Societies for Experimental Biology. Executive Summary from the Report: Analysis of Adverse Reactions to Monosodium Glutamate (MSG). J. Nutr. 125, 2891S-2906S (1995).
10. Kwok, R. H. M. Chinese Restaurant Syndrome. N. Engl. J. Med. 278:796, (Letter to the Editor) (1968).
13. Kenney, R. A. in Glutamic acid: advances in biochemistry and physiology (ed. Filer, L. J.) 363-373 (Raven Press, 1979).
14. Kenney, R. A. The Chinese Restaurant Syndrome: An anecdote revisited. Food and Chemical Toxicology 24, 351-354 (1986).