Monosodium glutamate, or MSG, is a bizarrely controversial food additive, isolated by Professor Kikunae Ikeda from kombu seaweed in 1908. Ikeda wanted to find out what was making his wife’s dashi taste so good and discovered that it was glutamic acid, an amino acid abundant in the dried seaweed, that was providing what he called the fifth taste, after salt, sweet, sour and bitter. That dreaded, overused word, ‘umami’. He called his discovery, Ajinomoto – ‘the essence of taste’.
The monosodium part of the name refers to common table salt which stabilises the glutamic acid so that it can be stored as a powder and easily added to foods. The professor found that just a sprinkle of this magical powder could transform even the drabbest dishes, imbuing them with a satisfying savouriness.
MSG is a flavour enhancer, so like salt, it improves the flavour of foods it is added to rather than adding much of its own. It’s the high levels of naturally occurring MSG in Parmesan cheese, sun-dried tomatoes, mushrooms and a whole load more of our favourite foods that give them their inexpressible deliciousness.
But wait. If you search for ‘MSG Hong Kong’ online, you’ll find hundreds of posts on forums about its negative effects: headaches, nausea, numbness and even depression. Here are some typical comments:
‘My husband is deeply allergic to MSG, will we be able to eat out when we visit Hong Kong?’
‘I always take a card with ‘please do not add MSG to my food’ written in Chinese and give it to the waiter. However, I can’t guarantee that you will avoid MSG that way.’
Hong Kong has a bad reputation for overusing the additive and it shows in the search results, they’re filled with worried statements like these, claiming that it’s impossible to find local food without MSG in the city. There are even reviews from leading magazines making claims like ‘the soup wasn’t fresh and was clearly full of MSG.’ But none of this is based on fact. This is just spurious opinion. People have no idea what goes into restaurant dishes so can they really be tasting MSG out of all the ingredients used?
Taken from a neutral perspective, this attitude is strange. Why so much drama over a naturally occurring amino acid stabilised with some salt? Glutamic acid is produced by our bodies and is present in virtually every type of protein we eat. It’s even found in breast milk. We need a certain amount of it to survive and it is a key compound in our cellular metabolism. MSG is chemically indistinguishable from the naturally occurring amino acid and is processed by our bodies in exactly the same way. So where did all this stuff about it being harmful come from?
It started in the 60s with a letter to the New England Journal of Medicine from a Chinese-American physician, Dr Ho Man Kwok. Kwok claimed he experienced headaches, numbness and heart palpitations after dining at Chinese restaurants in the US and speculated at the probable cause.
In his letter, he suggested common ingredients used in Chinese cooking like soy sauce might be to blame but said he ruled this out after using them at home with no ill effects. He suggested that it could just have been that he had too much rice wine with the meal but also speculated that MSG could be to blame and named his illness, ‘Chinese Restaurant Syndrome’. He didn’t offer any evidence that the food had MSG in it, but it was his speculation that MSG caused the symptoms that caught the public’s attention.
The idea quickly spread, as vacuous claims about health tend to, and others started to complain of symptoms ranging from nausea, headaches, back pain and numbness, to melancholy, listlessness and even depression. It seems strange that one ingredient could provoke this wide range of symptoms but that didn’t stop the gossip virus infecting more and more suggestable people.
A number of studies were subsequently funded trying to establish a link. Dr John W. Olney performed a study where he injected mice with doses of MSG and later found dead tissue in their brains. They also had problems with obesity, stunted growth and sterility later in life. But Dr Olney had injected a horse’s dose of MSG into these mice, and horses are around 50,000 times heavier than mice. If you injected that much of the mouse’s favourite cheese into it, it would probably cause problems too. He also delivered it directly into the flesh which isn’t how diners at Chinese restaurants usually take their egg fried rice.
After receiving criticisms such as these, he also gave smaller doses to rhesus monkeys orally and claims that he found the same results. But 19 other studies by other researchers failed to show the same or even similar results.
Over the years, numerous studies, funded by interested parties on both sides of the argument, failed to establish a link, but this didn’t stop the rumour mill churning out more stories about the ill effects of MSG. There were even anti-MSG cookbooks written and it was after this that many Chinese restaurants, trying to distance themselves from the outcry, started to advertise their food as ‘free from MSG’.
What’s always ignored is the fact that MSG is used as an additive in thousands of non-Chinese foods: Doritos, stock cubes, gravy powder, canned soups, KFC, Pringles and Cheetos, to name a few. Would the people who claim to get back pain after eating at a local Hong Kong restaurant get the same symptoms after scoffing a bucket of chicken or a bag of Doritos?
There’s nothing inherently wrong with food additives. The problem is that they’re usually used as a lazy replacement for fresh ingredients, which are more expensive and spoil quicker, so they tend to be associated with poor quality food with little nutrition.
The Food and Drug Administration or FDA, the US food industry’s regulator, after attempting to find a link between MSG and any of the reported symptoms for decades, has concluded that there is no link and MSG remains in category of foods ‘generally recognised as safe’.
This is from their website and is pretty conclusive: ‘Over the years, FDA has received reports of symptoms such as headache and nausea after eating foods containing MSG. However, we were never able to confirm that the MSG caused the reported effects.’
Most scientists agree that the idea of MSG causing negative symptoms in humans is totally unfounded. Many go further: “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.”
Unfortunately, fear-mongering posts online about the tons of MSG poured into every dish at every Chinese restaurant in the city and stories shared between friends about the terrible symptoms they experience, even if they are completely inconsistent with each other, tend to spread farther and faster than the results of scientific studies. So it looks like we’ll be burdened with this hysteria for years to come, and it will continue to have a negative impact on well-meaning local restaurants that probably don’t even use the magical powder.
Obviously, if you eat something and fall ill afterwards, you should find out what caused it and stop eating that thing. But if you come to Hong Kong and don’t eat at your neighbourhood dai pai dong because you’re worried about MSG, have you really experienced Hong Kong?
On that note, here’s our guide to the best cooked food centres in Hong Kong (which may or may not use MSG).