What is MSG?
We have all heard about MSG but what is it exactly and why is it thought to be a problem?
MSG = monosodium glutamate. This means that one sodium is bound to one glutamate.
Glutamates make up proteins and when released from proteins, the glutamates are called free glutamates.
Free glutamates make food very tasty. Free glutamates exist naturally in foods such as tomatoes, mushrooms and soy sauce or they can be added to foods (such as MSG) to boost flavour.
Glutamates can cause a range of issues if you are food chemical sensitive.
JOIN THE COMMUNITY: BRAND NEW Dietitian led Facebook group: Amines, Salicylates and Glutamates: The Food Intolerance Dietitian for great information and community support.
Brief History
For many years, the Japanese used a delicious broth called Dashi, made from boiled seaweed (kombu) and dried bonito fish (katsuobushi). A Japanese scientist in 1908 discovered that MSG was responsible for this delicious flavour and called this taste umami, from the Japanese word umami which means delicious.
MSG reactions first came under the spotlight in 1968 when Dr Kwok in New York wrote a letter to the editor of the New England Journal of Medicine about some strange symptoms he experienced after eating out in an American style Chinese restaurant.
The article prompted so many people to write in with their similar experiences that the Journal responded by labelling MSG as the likely suspect and termed this cluster of responses the 'Chinese Restaurant Syndrome'. Symptoms cited included headache, flushing, nausea, chest tightness and sweating.
Consequent scientific studies failed to reproduce these effects and public agencies around the world concluded MSG to be a safe additive, including the Australian regulatory body FSANZ (Food Standards Australia New Zealand)-
"MSG and other glutamates are among a group of food additives that are generally permitted in foods, due to their safety".
FSANZ goes on to acknowledge-
"A very small number of people who are sensitive to a range of foods, especially those with asthma, may be sensitive to glutamate"
So it is acknowledged that some people are sensitive to MSG and its closely related cousins (see below).
MSG Symptoms
More common symptoms reported:
Headaches and migraines
Flushing and sweating
Nausea
Chest tightness
Other reported reactions include:
Severe insomnia
Vivid nightmares
Itchy rashes
Heart palpitations or atrial fibrillation (irregular heart beats)
Depression
Abdominal pains, bowel pain, diarrhoea
Brain fog or an inability to think clearly
Arthritis
Asthma
Behaviour problems in children.
Foods Containing MSG
If you are sensitive to MSG then you are most likely also sensitive to:
Other glutamate additives and flavour enhancers (identified by name or number)
Free glutamates naturally found in foods
Glutamate Additives and Other Flavour Enhancers
The glutamate flavour enhancers include the food additive numbers 620 - 625. Food additive number 621 is MSG.
Other flavour enhancers include food additive numbers 627, 631, 635-637, 640-641. Of note is the flavour enhancer 635 (disodium ribonucleotides) which will amplify the effect of MSG.
So don't just avoid MSG but avoid all the flavour enhancers: glutamates (620- 625), other flavour enhancers (627, 631, 635 - 637) & flavour modifiers (640, 641).
GLUTAMATES:
620 L -glutamic acid
621 Monosodium L-glutamate or MSG
622 Monopotassium L- glutamate
623 Calcium glutamate
624 Monoammonium L-glutamate
625 Magnesium glutamate
OTHER FLAVOUR ENHANCERS:
627 Disodium guanylate
631 Disodium inosinate
635 Disodium ribonucleotides
636 Maltol
637 Ethyl maltol
FLAVOUR MODIFIERS:
640 Glycine
641 L-leucine
Free Glutamates in Food
Some foods are naturally high in free glutamates such as corn, peas, broccoli, spinach, mushrooms, strong cheeses (parmesan, camembert, brie & gruyere), soy sauce, oyster sauce, black bean sauce, tomato sauce, miso and plums.
Other food ingredients that contain MSG or other glutamates include:
Yeast extract, autolysed yeast, nutritional yeast, savoury yeast
Hydrolysed vegetable protein (HVP) or textured vegetable protein (TVP)
Autolysed or hydrolysed or lyophilised any protein
Vegetable: dehydrated, dehydrated seasoning
Extracts: vegetable, soy, yeast, meat, plant protein, any protein
Protein isolate
Intake of these foods or foods containing these ingredients may need to be reduced to manage food symptoms.
Free from MSG????
Foods are often promoted as being free from MSG. And it is true, there maybe no added MSG (621) but...
Check the ingredient list-there may be other glutamate additives or flavour enhancers added that have been used instead.
Or ingredients that naturally contain glutamates (including monosodium glutamate) such as soy sauce powder, cheese powder vegetable and dehydrated vegetable seasoning.
An ingredient does not need to state if it contains natural glutamates so these sources remain unlisted or hidden.
Note that flavour enhancers are added to nearly all savoury snack foods and include flavoured crisps/chips, biscuits and 2 minute noodles.
Eating Out
Restaurants and cafes do not need to declare the presence of MSG and the other similar additives.
So you need to ask- always!
Main Points
If you react to MSG you may also react to other glutamate additives and flavour enhancers added to foods, as well as naturally occurring free glutamates in foods foods.
A food being that may be free from MSG (621) may have other flavour enhancers added or have an ingredient such as soy sauce powder which contains glutamates. Check the ingredient list carefully.
As a rule, savoury foods will contain glutamates through one source or another.
Updated 18th July 2018.
REFERENCES
The Conversation. Monday's medical myth- MSG is a dangerous toxin. 2011-12-12. Retrieved from: http://theconversation.com/mondays-medical-myth-msg-is-a-dangerous-toxin-4560. Retrieved on 2017-02-15.
Mayo Clinic. Healthy Lifestyle. Nutrition and Healthy eating. Katherine Zeratsky. Retrieved from: http://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/expert-answers/monosodium-glutamate/faq-20058196. Retrieved on: 2017-02-15.
RPAH Food Intolerance Handbook Volume II: Challenges, liberalising & management. Anne Swain, Valencia Soutter, Robert Loblay Allergy, Unit Royal Prince Alfred Hospital 2016.
Food Intolerance Network. 129 ways to add msg and fool consumers, Howard Dengate (no date given). https://fedup.com.au/news/blog/129-ways-to-add-msg-and-fool-consumers. Retrieved on: 2018-07-18
Catherine Saxelby's Food Watch. 2014-06-13.Retrieved from: http://foodwatch.com.au/blog/additives-and-labels/item/q-some-foods-are-labelled-no-msg-what-does-msg-stand-for-and-is-it-bad-for-our-health.html. Retrieved on: 2017-02-16.6. Smithsonian.com.
It's the Umami, Stupid. Why the Truth About MSG is So Easy to Swallow. Natasha Geiling. 2013-11-08.Retrieved from: http://www.smithsonianmag.com/arts-culture/its-the-umami-stupid-why-the-truth-about-msg-is-so-easy-to-swallow-180947626/. Retrieved on 2017-02-15.