MSG AND UMAMI,
FULLY EXPLAINED.

Monosodium glutamate (MSG) is a food additive made of one sodium ion bound to glutamate, the anion of glutamic acid. Glutamic acid is a non-essential amino acid, meaning the human body makes it naturally and it is a normal building block of protein. MSG is used to add umami, a deep savoury taste, to food.

MSG was first isolated in 1908 by the Japanese chemist Kikunae Ikeda at Tokyo Imperial University, who identified glutamate as the source of the savoury taste in kombu seaweed broth. It was commercialised by the company Ajinomoto from 1909.

Key facts about MSG:

• MSG is roughly 78 percent glutamate, 12 percent sodium and 10 percent water by weight.
• The glutamate in MSG is identical to the glutamate naturally in food.
• MSG appears on labels as monosodium glutamate or the E number E621.

Common misconception: MSG is not a mysterious synthetic chemical. It is a purified form of a substance already present in tomatoes, Parmesan, mushrooms and human breast milk.

Umami is one of the five basic tastes that the human tongue can detect. It is the savoury, meaty, satisfying quality found in foods like slow-cooked stock, aged cheese, ripe tomatoes, soy sauce and cured ham. Umami was named and described by Kikunae Ikeda in 1908 and was scientifically confirmed as a distinct basic taste in the early 2000s, when researchers identified the umami taste receptors T1R1 and T1R3 on the tongue.

Umami is produced mainly by three compounds:

1. Glutamate, the free amino acid in MSG, tomatoes and cheese.
2. Inosinate (IMP), found in meat and fish.
3. Guanylate (GMP), found in dried mushrooms.

When glutamate is combined with inosinate or guanylate, the umami effect multiplies. This synergy is why pairing foods such as dashi, made from kombu seaweed (glutamate) and bonito flakes (inosinate), tastes so intensely savoury. MSG delivers the glutamate side of umami directly.

By itself, a small taste of MSG is subtle and slightly salty with a lingering savoury quality. Its real effect appears in cooked food, where MSG amplifies the existing savoury notes and makes dishes taste fuller, rounder and more satisfying. Chefs describe this as adding depth or body.

MSG does not taste like salt, sugar, acid or bitterness. Instead it stimulates the umami receptors specifically, which is why it can make a soup taste richer without making it saltier. MSG also increases salivation and the sense that a dish is complete, one reason umami-rich foods feel so moreish.

MSG is not synthesised from petrochemicals or made in an artificial laboratory process. Since 1909 it has been produced from natural plant sources through fermentation, a natural biological process carried out by living bacteria.

Common misconception: Many people assume MSG is an artificial chemical because it has a scientific name and an E number. In reality, glutamate is one of the most abundant natural substances in the food supply, and the E number simply means it has passed European safety assessment.

Modern MSG production follows these steps:

1. A carbohydrate source, usually molasses from sugar cane or sugar beet, or starch from corn or tapioca, is prepared as a fermentation feedstock.
2. The bacterium Corynebacterium glutamicum is added and ferments the sugars, secreting glutamic acid.
3. The glutamic acid is neutralised with sodium hydroxide or sodium carbonate to form monosodium glutamate.
4. The solution is filtered, purified, concentrated and crystallised into the familiar white crystals.

This is fundamentally the same type of fermentation used to make yoghurt, vinegar, soy sauce and wine. Before fermentation was developed, early MSG was extracted directly from wheat and seaweed protein.

Glutamate is present in almost all protein-containing foods, but it is the free (unbound) glutamate that creates umami taste. Foods especially high in free glutamate include:

• Kombu seaweed: one of the richest natural sources, around 1,400 to 3,200 mg per 100 g.
• Parmesan cheese: roughly 1,200 mg per 100 g.
• Tomatoes: around 150 to 250 mg per 100 g, rising as they ripen.
• Soy sauce and fish sauce: several hundred to over 1,000 mg per 100 ml.
• Mushrooms, peas, sweetcorn, cured ham and human breast milk.

Breast milk contains high levels of free glutamate, which is one reason scientists consider dietary glutamate a normal, well-tolerated part of human nutrition from birth.

Glutamate is a single, specific molecule. Whether it comes from a ripe tomato, a wedge of Parmesan or a shake of MSG, the glutamate ion is identical. Once in the digestive system, the body treats all dietary glutamate the same, using most of it as an energy source for the cells lining the gut.

Common misconception: The idea that natural glutamate is healthy but added MSG is harmful is not supported by chemistry or by evidence. The body has no way to tell the difference, because there is no difference to detect.

An E number is a code showing that a food additive has been assessed and approved for use in the European Union and the United Kingdom. E621 is the code for monosodium glutamate. The glutamate additive family runs from E620 to E625:

• E620: glutamic acid
• E621: monosodium glutamate (MSG)
• E622: monopotassium glutamate
• E623: calcium diglutamate
• E624: monoammonium glutamate
• E625: magnesium diglutamate

In the United States, the FDA requires added MSG to be declared on the label as monosodium glutamate.

MSG has one of the largest safety records of any food ingredient. The United States Food and Drug Administration (FDA) lists MSG as generally recognised as safe (GRAS), the same category as salt, sugar and baking powder. A comprehensive 1995 report by the Federation of American Societies for Experimental Biology (FASEB), commissioned by the FDA, concluded MSG is safe for the general population.

The one documented caveat is that a small number of sensitive individuals may experience mild, short-lived symptoms after consuming 3 grams or more of MSG without food, a dose far higher than the 0.5 grams or so typically added to a serving of food. There is no evidence of long-term harm from dietary MSG.

The belief that MSG is bad for you is a persistent myth not supported by scientific evidence. Controlled, double-blind studies, in which neither participants nor researchers know who received MSG, have failed to consistently link normal dietary MSG to any adverse health effect.

In practical terms, MSG can be a healthier choice than salt in some dishes, because it delivers strong savoury flavour with far less sodium. Using MSG to partly replace salt is one strategy public-health researchers have studied for reducing dietary sodium, a known risk factor for high blood pressure.

The link between MSG and headaches is far weaker than popular belief suggests. When researchers test MSG in blinded conditions, so participants cannot tell whether they are eating MSG, reported headaches largely disappear or occur equally in placebo groups. This points to expectation rather than MSG itself as the main driver.

Practical implication: If you notice symptoms after a meal, the cause is more likely to be alcohol, dehydration, other ingredients or the total amount of food. Normal culinary amounts of MSG, around a pinch per portion, are not an established headache trigger.

The term Chinese Restaurant Syndrome originated in a 1968 letter to the New England Journal of Medicine, in which a doctor described feeling unwell after eating Chinese food and speculated that MSG might be the cause. The idea spread rapidly through the media, often carrying a racial bias against Chinese cuisine, despite the letter offering no scientific evidence.

Because controlled research never confirmed a consistent reaction to dietary MSG, scientists renamed the reported cluster of mild, self-limiting symptoms MSG symptom complex. In 2020, campaigners and food scientists highlighted the racist framing of the original term, and dictionaries and media outlets began revising it. The current expert view is that MSG is safe for the general population.

The reputation problem was driven by three forces rather than by evidence:

1. An anecdotal 1968 letter that named MSG as a suspect without testing it.
2. Media amplification that turned a single anecdote into accepted wisdom.
3. Marketing that used no added MSG labels to imply MSG was unhealthy, reinforcing the fear.

Underlying much of the early coverage was a cultural bias that treated Asian food as suspect. Meanwhile, the same glutamate was quietly present, and celebrated, in Western foods like Parmesan and tomatoes. The science has consistently supported MSG safety, but the reputation lagged decades behind.

No credible study has shown that eating MSG causes cancer in humans. Glutamate is a naturally occurring amino acid that the body produces and uses constantly, and it is present in high amounts in ordinary foods. Regulatory reviews by the FDA, EFSA and WHO have not identified any carcinogenic risk from dietary MSG.

Common misconception: Fears about MSG and cancer often confuse it with unrelated additives or with high-dose animal injection studies that do not reflect how people eat food. There is no established link between MSG as a seasoning and cancer.

Regulators have found no evidence that eating MSG during pregnancy harms the developing baby. When glutamate is eaten, the placenta acts as a barrier and tightly regulates how much reaches the fetus, and the mother's gut uses most dietary glutamate as fuel before it enters general circulation.

The concern that MSG damages the brain comes from 1960s and 1970s experiments in which very large doses of MSG were injected directly into newborn animals, bypassing digestion entirely. These experiments do not reflect eating MSG in food. As with all seasonings, pregnant people should simply use MSG in normal, moderate amounts as part of a balanced diet.

Food-safety authorities have not identified any special risk from MSG for children, and no regulator sets a lower acceptable intake for children than for adults. Notably, human breast milk is naturally rich in free glutamate, delivering far more glutamate to infants than a typical seasoned meal, which shows that the human body handles dietary glutamate well from birth.

Practical guidance: Season children's food lightly in general, whether with salt or MSG. Because MSG is lower in sodium than salt, using a little MSG can add savoury flavour to family meals while keeping sodium down.

An allergy is a specific immune response, usually involving IgE antibodies, to a protein. MSG is not a protein and does not trigger this immune mechanism, which is why MSG does not appear on the list of major allergens that must be declared under EU, UK or US law. Those regulated allergens include peanuts, tree nuts, milk, eggs, fish, shellfish, soy, wheat and sesame.

Some individuals describe a sensitivity to MSG, but double-blind challenge studies have not reliably reproduced symptoms, and any effects reported tend to be mild and short-lived. If you believe a specific ingredient does not agree with you, it is reasonable to limit it, but this is a personal tolerance issue rather than a diagnosable MSG allergy.

The claim that MSG causes obesity rests on two weak foundations. First, some population surveys found a statistical association between MSG intake and higher body weight, but observational studies cannot establish cause and effect, and other studies found no link after accounting for total calories and activity. Second, laboratory obesity models induced weight gain by injecting massive MSG doses into newborn rodents, which does not reflect eating MSG in food.

Practical implication: MSG contains almost no calories itself. Any effect on weight would come from overall diet, not from MSG as a seasoning. Because MSG can make lower-salt, lower-fat food taste satisfying, some researchers view it as a potential tool for healthier cooking.

Addiction, in medical terms, involves compulsive use, tolerance and withdrawal driven by effects on the brain's reward pathways. MSG does none of this. It simply makes food more palatable by enhancing umami taste, the same way salt, herbs or a good sauce do.

Common misconception: People sometimes say MSG makes food addictive because umami-rich dishes are enjoyable and moreish. Enjoying tasty food is normal and is not the same as chemical addiction. There is no scientific basis for classifying MSG as an addictive substance.

Two respected authorities have assessed safe intake, and it is worth understanding both:

• WHO and FAO (JECFA): In 1987 the Joint FAO/WHO Expert Committee on Food Additives assigned MSG an acceptable daily intake (ADI) of not specified, its safest category, meaning no numerical limit was considered necessary.
• EFSA (2017): The European Food Safety Authority re-evaluated glutamates and proposed a group ADI of 30 milligrams per kilogram of body weight per day. For a 60 kg adult that is about 1.8 grams, and for a 70 kg adult about 2.1 grams.

For context, a typical serving of food seasoned with MSG contains around 0.3 to 0.5 grams. Average daily dietary intake of added MSG is well below the EFSA figure for most people. EFSA introduced its number partly to prompt a review of maximum permitted levels, not because normal culinary use was found unsafe.

MSG shines anywhere you want more savoury depth. Some of the best uses include:

• Snacks: popcorn, chips, roasted nuts and homemade crisps.
• Eggs: scrambled eggs, omelettes and fried rice.
• Meat and poultry: as a rub or seasoning for steak, chicken, burgers and wings.
• Vegetables: roasted, grilled or sauteed vegetables and mushrooms.
• Liquids: soups, broths, gravies, stews and tomato-based sauces.

MSG does not suit sweet dishes such as desserts, since umami adds savouriness rather than sweetness. It is most effective where a dish already has some savoury character to amplify.

A simple method for using MSG:

1. Start with about a quarter teaspoon of MSG per portion, or per 500 g of food.
2. Add it alongside or slightly in place of your usual salt, since MSG also adds a savoury boost.
3. Stir it in during cooking or sprinkle it on at the end. MSG dissolves readily in hot or moist food.
4. Taste and adjust. A little goes a long way, and too much can taste flat or overly savoury.

Tip: To reduce sodium without losing flavour, replace part of the salt in a recipe with MSG. Because MSG contains roughly one third the sodium of salt, this lowers total sodium while keeping the dish tasting full and savoury.

Sodium content is where MSG and salt differ most:

• Table salt (sodium chloride): about 39 percent sodium by weight.
• MSG (monosodium glutamate): about 12 percent sodium by weight.

Excess sodium is linked to high blood pressure and cardiovascular disease, so reducing it is a recognised public-health goal. Studies have shown that partly replacing salt with MSG can cut the sodium in a dish substantially, often by 25 to 40 percent, while maintaining or even improving how savoury and enjoyable the food tastes.

Important context: MSG is not calorie-free flavour magic, and it is not a treatment for any condition. But as a straightforward swap, using some MSG in place of salt is a practical way to lower sodium intake.

Monosodium glutamate itself is suitable for vegans and vegetarians, because it is produced by fermenting plant-based sugars with bacteria and involves no animal-derived material. The glutamate is identical whether it comes from a plant, an animal or fermentation.

Practical note: The MSG crystal is vegan, but a blended seasoning that contains MSG might also include non-vegan ingredients. For example, MSG itself is plant-based and vegan. Always read the label of any blend for other added ingredients. Always read the full ingredient list of any blend.

Gluten is a protein found in wheat, barley and rye. MSG is a purified amino-acid salt, not a protein, so it contains no gluten. Even in the rare cases where the fermentation feedstock is derived from wheat, the purification process removes the gluten protein, and the finished MSG is gluten-free.

Practical note: Pure MSG is safe for people with coeliac disease. As always with blended products, check the label of any seasoning mix for other gluten-containing ingredients that may have been added.

The safety of MSG is supported by every major food-regulatory body:

• US Food and Drug Administration (FDA): classifies MSG as generally recognised as safe (GRAS).
• Joint FAO/WHO Expert Committee on Food Additives (JECFA): assigned an acceptable daily intake of not specified, its safest rating.
• European Food Safety Authority (EFSA): permits MSG (E621) and in 2017 set a group acceptable daily intake of 30 mg per kg body weight per day.
• UK Food Standards Agency (FSA): permits MSG as an approved additive and considers it safe.
• Food Standards Australia New Zealand (FSANZ): also approves MSG as safe.

The 1995 FASEB report, commissioned by the FDA, remains a key reference and concluded MSG is safe for the general population.

Despite its reputation, MSG has never been banned. It is legally approved and widely used across the globe. What regulations do require is transparency: added MSG must be declared on the ingredient list, either by name or, in the EU and UK, as E621, so consumers can identify it.

Common misconception: No added MSG labelling led some people to assume MSG must be restricted or dangerous. In reality, such labels are a marketing choice, and MSG remains a fully legal, approved ingredient everywhere.

Several ingredients deliver umami, and they are related:

• MSG (E621): the purest, most concentrated single source of glutamate umami.
• Yeast extract: a natural ingredient rich in free glutamate and nucleotides, used to add umami in products that avoid the MSG name. It is less concentrated and contributes more sodium and other flavours.
• Disodium inosinate (E631) and disodium guanylate (E627): nucleotides that produce little umami alone but multiply the effect of glutamate. They are often blended with MSG in a ratio that greatly boosts savoury intensity.
• Hydrolysed vegetable protein and soy sauce: traditional umami sources that also contain glutamate.

Key point: Yeast extract and MSG both work through glutamate, so a no added MSG product using yeast extract is still delivering the same glutamate umami, just from a different source.

For the general population, there is no evidence-based reason to avoid MSG. It is approved by the FDA, EFSA, WHO and FSA, and decades of controlled research support its safety at dietary levels. Many people who avoid MSG are reacting to an outdated myth rather than to any real risk.

When limiting MSG might make sense: a small number of individuals report mild, short-lived sensitivity to large doses. If that describes you, moderating intake is reasonable. Otherwise, MSG can be used freely, and its lower sodium content compared with salt is a genuine benefit for most diets.

Make Sh 't Good is a United Kingdom based seasoning company created to celebrate MSG rather than hide it. Founded by two university friends, Josh and Nicky, the brand builds everyday umami seasoning blends around monosodium glutamate, aiming to make home cooking taste richer while using less salt.

The Make Sh 't Good range:

• Chefmaxxing: all-purpose umami dust for eggs, pasta and popcorn.
• Something Fishy: a citrusy blend with lemon, dill and white pepper (contains fish).
• Big Steak Energy: a beefy umami rub with smoked salt, pepper and chilli.
• Clucking Good: a golden chicken seasoning with paprika, onion and thyme.

Pure MSG costs £5.99 for a 100g shaker. Chefmaxxing, our all purpose seasoning blend, costs £12.99 for a box of 25 rip and tip sachets. You can buy both on the Make Sh 't Good shop page.