What Is MSG? Myths, Facts, and the Science Behind this Savoury Food Enhancer
If you’ve ever seen monosodium glutamate (MSG) listed on a food label and wondered whether it’s safe, or why it’s used at all, you’re not alone. Over decades, MSG has become one of the most misunderstood ingredients in the culinary world. Let’s unpack what it really is, explore the myths versus the evidence, and show how it can make food oh-so-much-more delicious!
History and How MSG is Made
In 1908 Japanese biochemist, Kikunae Ikeda, extracted glutamate from a seaweed broth to produce the first man-made MSG.
MSG is produced via fermentation, using starches, sugar cane, molasses, or corn as starting material. This fermentation process is similar to the processes we use to make yoghurt, vinegar, and many other fermented foods.
So, What Actually Is MSG?
MSG is simply the sodium salt of the amino acid glutamate (a salt form of glutamic acid). In nature, glutamate is found in many foods like meat, cheese, mushrooms, tomatoes, and more. Free glutamate (i.e. unbound to other amino acids) stimulates our “umami” receptors, giving that deep, savoury flavour sensation that we love and crave.
When glutamate is crystallised with sodium, you get MSG, a white (or translucent) crystal-like substance that looks a bit like salt or sugar in. The body processes glutamate from MSG the same way it processes glutamate from natural foods, it doesn’t distinguish the source and it metabolises them the same.
What the Science and Authorities Say
Modern science has since proven that MSG is perfectly safe to consume in moderation, however, as with any food, some people may have an adverse reaction.
The U.S. Food and Drug Administration (FDA) classifies MSG as “generally recognised as safe” (GRAS), meaning that experts consider it safe to eat in normal quantities. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) and other international bodies have similarly found no credible evidence that MSG poses health risks in typical dietary use.
A safety review of MSG concluded that it’s safe across all life stages, with no clear evidence of harm to the nervous, endocrine, reproduction, or development systems.
The Origins of the MSG Backlash
MSG’s reputation took a sharp turn in 1968, when a doctor penned a letter to the New England Journal of Medicine describing symptoms like headaches, numbness, and palpitations, after eating at Chinese restaurants. He speculated MSG might be responsible, and the phrase “Chinese Restaurant Syndrome” (CRS) was born.
That letter, though speculative and anecdotal, sparked widespread fear and stigma. Over time, MSG was painted as an unnatural, dangerous additive, especially in Western contexts. But as more rigorous studies emerged, most of those fears failed scientific scrutiny.
Clinical Evidence & Sensitivity Claims
Many studies have attempted to reproduce the symptoms, but the results are inconsistent. In well-controlled trials where MSG is consumed with food, few (if any) participants reliably report adverse effects.
A comprehensive review concluded that typical dietary intakes of MSG are unlikely to cause adverse effects, and that many earlier studies showing reactions used abnormally high doses or lacked proper controls.
For most of us, MSG is safe in normal amounts when used for cooking or other culinary uses. However, as with any sensitivity, if you suspect you have an MSG sensitivity, be cautious and limit high-MSG foods to see whether symptoms improve.
Common Myths & Clarifications
Myth 1: MSG is an artificial or chemical “toxin”
Reality: MSG is produced via fermentation and is basically the same molecule as natural glutamate. Its safety has been assured by multiple regulatory agencies.
Myth 2: Eating MSG causes obesity or other chronic disease
Reality: There is no consistent or convincing evidence to suggest that MSG directly causes obesity, diabetes, or metabolic disorders. Some observational studies suggest correlations, but this is often because diets high in MSG often go hand-in-hand with diets that contain a lot of highly processed, calorie-dense foods.
Myth 3: Everyone who complains of MSG reactions is correct
Reality: While some people report discomfort, controlled studies fail to reliably reproduce symptoms when variables are controlled. In many cases, the reported symptoms may be influenced by expectation or nocebo effects (i.e. people expect to feel bad and then do).
Myth 4: MSG must be avoided entirely
Reality: Because glutamate is in natural, wholesome foods avoiding MSG doesn’t meaningfully reduce glutamate intake. What matters more is overall diet quality.
MSG vs Salt: A Low-Sodium Alternative
You’ve probably eaten MSG without realising it. Many umami-rich ingredients already contain free glutamate, like soy sauce, tomato paste, parmesan cheese, mushrooms, and even aged meats. Because MSG boosts flavour, it’s means you can reduce the amount of salt needed while still making food tasty (MSG contains about one-third the sodium of sodium chloride by weight.)
How MSG Enhances Taste (and Makes Food Better)
The umami flavour dimension is described as savoury, meaty, or mouth-filling. MSG enhances umami by activating specific receptors on the tongue, deepening the sensory experience of other flavours without necessarily making the food “salty” on its own.
Here’s how using MSG in moderation can elevate your cooking:
Brightens other ingredients: A pinch of MSG can make vegetables, meats, broths, or sauces taste more vivid and nuanced, adding layers and depth of flavour that would otherwise be missed.
Helps in plant-based or low-fat cooking: When fat or meat are minimised, MSG can restore depth and “meatiness” to legumes, mushrooms, tofu, or vegetable stews.
Works in small doses: You don’t need much; recipes often call for ¼ to ½ teaspoon for a dish serving multiple people.
Tips for Using MSG Sensibly
- Add it late: Sprinkle it near the end of cooking to preserve its delicate flavour-enhancing effect.
- Start small: Use just a pinch. It’s easier to add more than to fix over-seasoning.
- Pair it with salt reduction: Reduce table salt proportionally so the overall sodium load isn’t too high.
- Balance flavours: Ensure your dish has acidity, fat, texture, or herbs to balance the richness.
Why MSG Deserves Another Look
Rather than demonising MSG, the current consensus is clear: in typical culinary amounts, MSG is safe for most people. Its earlier negative reputation was built on shaky science, cultural bias, and sensationalism more than solid evidence.
For cooks, MSG is a cost-effective, powerful tool to enhance flavour, especially in dishes that lack strong umami, such as vegetarian, low-fat, or lean-protein recipes. Used smartly, it lets you lighten salt use while still making sure your food is super tasty, arguably, even more tasty than using salt alone!
This content is for general information only and does not replace professional medical advice.