MSG is back. Is the idea it’s bad for us just a myth or food science?
<p><em><a href="https://theconversation.com/profiles/evangeline-mantzioris-153250">Evangeline Mantzioris</a>, <a href="https://theconversation.com/institutions/university-of-south-australia-1180">University of South Australia</a></em></p>
<p>MSG is making a comeback. The internet’s favourite cucumber salad recipe includes fish sauce, cucumber, garlic and – as the video’s creator Logan tells us with a generous sprinkle from the bag – “MSG, obviously”.</p>
<p>But for many of us, it’s not obvious. Do you have a vague sense MSG is unhealthy but you’re not sure why? Here is the science behind monosodium glutamate, how it got a bad rap, and whether you should add it to your cooking.</p>
<h2>What is MSG?</h2>
<p>Monosodium glutamate (MSG) is a sodium salt of glutamic acid, one of the amino acids that make up proteins.</p>
<p>It occurs naturally in <a href="https://www.tandfonline.com/doi/full/10.1080/10942912.2017.1295260#d1e167">foods</a> such as mature cheeses, fish, beef, mushrooms, tomatoes, onion and garlic. It provides their savoury and “meaty” flavour, known as <a href="https://www.sciencedirect.com/science/article/pii/S0022316622140186">umami</a>.</p>
<p>MSG has been used to season food for <a href="https://wjpsonline.com/index.php/wjps/article/view/effects-monosodium-glutamate-human-health-review">more than 100 years</a>. Traditionally it <a href="https://pubs.acs.org/doi/epdf/10.1021/ed081p347?ref=article_openPDF">was extracted</a> from seaweed broth, but now it’s made by fermenting starch in sugar beets, sugar cane and molasses.</p>
<p>Today it’s widely used as a flavour enhancer in many dishes and pre-packaged goods, including soups, condiments and processed meats.</p>
<p>There is no chemical difference between the MSG found in food and the additive.</p>
<h2>Is it safe?</h2>
<p>For most people, yes. MSG is a safe and authorised additive, according to the Australian agency that regulates food. This corresponds with food standards in the <a href="https://www.fda.gov/food/food-additives-petitions/questions-and-answers-monosodium-glutamate-msg">United States</a>, <a href="https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=CELEX%3A02008R1333-20201223#tocId3">European Union and United Kingdom</a>.</p>
<p>Two major <a href="https://www.foodstandards.gov.au/sites/default/files/consumer/additives/msg/Documents/MSG%20Technical%20Report.pdf">safety reviews</a> have been conducted: one in 1987 by a United Nations expert committee and another 1995 by the Federation of American Societies for Experimental Biology. Both concluded MSG was safe for the general population.</p>
<p>In 2017 the <a href="https://www.efsa.europa.eu/en/efsajournal/pub/4910">European Food Safety Authority</a> updated its stance and set a recommended limit based on body weight, aimed to prevent headaches and increased blood pressure.</p>
<p>That limit is still higher than most people consume. The authority says an 80kg person should not have more than 2.4g of added MSG per day. <a href="https://www.nature.com/articles/1602526">For reference</a>, Europeans average less than a gram per day (0.3-1 gram), while in Asia intake is somewhere between 1.2-1.7 grams a day.</p>
<p>Food Standards Australia New Zealand says the European update does not raise any new safety concerns not already assessed.</p>
<h2>Isn’t it bad for me?</h2>
<p>Despite the evidence, the idea MSG is dangerous persists.</p>
<p>Its notorious reputation can be traced back to a <a href="https://news.colgate.edu/magazine/2019/02/06/the-strange-case-of-dr-ho-man-kwok/">hoax letter</a> published in the <a href="https://www.nejm.org/doi/full/10.1056/NEJM196805162782014">New England Journal of Medicine</a> in 1968. A doctor claiming to have experienced palpitations, numbness and fatigue after eating at a Chinese restaurant suggested MSG could be to blame.</p>
<p>With a follow-up article in the <a href="https://www.nytimes.com/1968/05/19/archives/-chinese-restaurant-syndrome-puzzles-doctors.html">New York Times</a>, the idea of “Chinese Restaurant Syndrome” took off. Eating MSG was associated with a range of symptoms, including headache, hives, throat swelling, itching and belly pain.</p>
<p>However an <a href="https://www.sciencedirect.com/science/article/pii/027869159390012N?via%3Dihub">early randomised control trial</a> showed no difference in these symptoms between people who were given MSG versus a placebo. This has since been confirmed in a <a href="https://ift.onlinelibrary.wiley.com/doi/full/10.1111/1541-4337.12448">review of many studies</a>.</p>
<h2>Can MSG cause reactions?</h2>
<p>A very small percentage of people may have hypersensitivities to MSG. The reported reaction is now known as MSG symptom complex, rather than so-called Chinese restaurant syndrome, with its <a href="https://www.jandonline.org/article/S2212-2672(21)00068-X/abstract#:%7E:text=A%20New%20York%20Times%20piece,connecting%20MSG%20to%20health%20outcomes.">problematic</a> racial connotations. Symptoms are usually mild, short-term and don’t need treatment.</p>
<p><a href="https://www.sciencedirect.com/science/article/pii/S0091674999703714">One study</a> looked at 100 people with asthma, 30 of whom believed they had hypersensitivities to MSG. However when participants were blinded to whether they were consuming MSG, not one reported a reaction.</p>
<p>If you believe you do react to added MSG, it’s relatively easy to avoid. In Australia, it is <a href="https://www.foodstandards.gov.au/consumer/additives/msg">listed</a> in ingredients as either monosodium glutamate or flavour enhancer 621.</p>
<h2>Is it better than table salt?</h2>
<p>Using MSG instead of regular salt may help <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6893472/">reduce</a> your overall sodium intake, as MSG <a href="https://www.medicalnewstoday.com/articles/msg-what-the-science-says-about-its-safety#Uses-of-MSG">contains</a> about one third the amount of sodium.</p>
<p><a href="https://pubmed.ncbi.nlm.nih.gov/21372742/">One study</a> found people who ate soup seasoned with MSG rather than salt actually liked it more. They still found it salty to taste, but their sodium intake was reduced by 18%.</p>
<p>MSG still contains sodium, so high use is associated with increased <a href="https://pubmed.ncbi.nlm.nih.gov/21372742/">blood pressure</a>. If you’re using MSG as a substitute and you have high blood pressure, you should closely monitor it (just as you would with other salt products).</p>
<h2>Should I use MSG in my cooking?</h2>
<p>If you want to – yes. Unless you are one of the rare people with hypersensitivities, enhancing the flavour of your dish with a sprinkle of MSG will not cause any health problems. It could even help reduce how much salt you use.</p>
<p>If you’re <a href="https://www.tandfonline.com/doi/full/10.1080/25765299.2020.1807084#d1e199">vegetarian or vegan</a>, cooking with MSG could help add the umami flavour you may miss from animal products such as meat, fish sauce and cheese.</p>
<p>But buying foods with added MSG? Be aware, many of them will also be <a href="https://www.cambridge.org/core/journals/public-health-nutrition/article/un-decade-of-nutrition-the-nova-food-classification-and-the-trouble-with-ultraprocessing/2A9776922A28F8F757BDA32C3266AC2A">ultra-processed</a> and it’s that – not the MSG – that’s associated with poor physical and mental <a href="https://www.mdpi.com/2072-6643/14/1/174">health outcomes</a>.<img style="border: none !important; box-shadow: none !important; margin: 0 !important; max-height: 1px !important; max-width: 1px !important; min-height: 1px !important; min-width: 1px !important; opacity: 0 !important; outline: none !important; padding: 0 !important;" src="https://counter.theconversation.com/content/237871/count.gif?distributor=republish-lightbox-basic" alt="The Conversation" width="1" height="1" /></p>
<p><em><a href="https://theconversation.com/profiles/evangeline-mantzioris-153250">Evangeline Mantzioris</a>, Program Director of Nutrition and Food Sciences, Accredited Practising Dietitian, <a href="https://theconversation.com/institutions/university-of-south-australia-1180">University of South Australia</a></em></p>
<p><em>Image credits: Shutterstock </em></p>
<p><em>This article is republished from <a href="https://theconversation.com">The Conversation</a> under a Creative Commons license. Read the <a href="https://theconversation.com/msg-is-back-is-the-idea-its-bad-for-us-just-a-myth-or-food-science-237871">original article</a>.</em></p>