In 1908, Japanese scientist Kikunae Ikeda was brewing seaweed soup when he asked a question that changed the food industry forever. Ikeda was trying to figure out why his vegetarian soup tasted like meat.

After a series of chemical experiments over several days, isolating the core substance of a seaweed called Laminaria japonica, the scientist observed the development of a crystalline form.

When they sampled the crystals, they immediately recognized the unique delicious flavor in the seaweed soup that was added to various dishes, a taste they named umami, derived from the Japanese word umai (delicious). They identified the molecular formula of the crystals, which matched that of glutamic acid, a non-essential amino acid produced by the body.

This discovery shook the foundations of culinary understanding: instead of the four basic tastes – sweet, salty, bitter and sour – there were now five.

Ikeda immediately took advantage of this new dimension of flavor and, the following year, began mass-producing Ajinomoto, the sodium salt form of glutamic acid that enhances the flavor of food, a compound we now call monosodium glutamate, or MSG.

The MSG Conundrum

Monosodium glutamate, commonly known as MSG, is a flavor enhancer found in many foods. Despite its widespread use, it has been the subject of much debate and scrutiny. It gained infamous status several years ago when manufacturers began selling food products labeled “No MSG,” indicating that the product was safe for consumption.

However, researchers have found that MSG being considered a healthier option is just a food myth. Rumors about cancer, brain disorders, migraines, and fevers were blamed on this controversial food additive.

But now MSG is back and enough studies have been done to support claims that the substance is “safe.” The U.S. Food and Drug Administration (FDA) classifies MSG as “generally recognized as safe” (GRAS).

The FDA reports that consuming large amounts of MSG on an empty stomach – 3 grams or more – can cause headaches and nausea. However, most prepared foods and recipes typically contain half a gram or less.

The Joint FAO/WHO Expert Committee on Food Additives (JECFA) has set an acceptable daily amount (ADI) of 30 mg per kilogram of body weight, which is well above normal dietary intake levels.

Although the myths persist, research has proven many of them wrong.

A systematic review published in 2000 in the Journal of Nutrition evaluated the safety of MSG consumption in both animals and humans.

Toxicity studies on various animal species showed no harmful effects. Similarly, human studies also confirmed the safety of this additive, except for a small group that exhibited sensitivity to MSG.

For example, some people claim to experience “Chinese restaurant syndrome” symptoms after consuming MSG, such as headache, dizziness, sweating, stomach pain, and bile, but this is not supported by scientific evidence.

In India, as per FSSAI regulations, MSG is an approved food additive and is permitted under GMP – Good Manufacturing Practices.

Could MSG solve the world’s sodium crisis?

Since it is a food flavouring, experts are now researching whether MSG could become a healthier alternative to table salt to reduce high sodium levels in the general population, which can cause heart problems and stroke.

MSG, a naturally occurring compound found in various foods, contains glutamate or glutamic acid, one of the most common amino acids in nature and found in many natural foods, such as tomatoes, mushrooms, broccoli, peas, fish, soy sauce, and aged cheeses.

Even human breast milk is rich in glutamate.

Dr Jamuna Prakash, former professor and food consultant, Department of Food Science and Nutrition, University of Mysore, said the production of MSG is similar to the fermentation process used to make curd.

“Plant-based raw materials such as sugarcane, beetroot or cassava are fermented with the help of fermentative microorganisms. These microorganisms absorb the glucose and release glutamic acid, which through neutralisation is converted into a solution containing MSG. This pure solution is crystallised to form the final product – MSG,” Dr Prakash told IndiaToday.in.

The World Health Organization (WHO) recommends adults eat less than 5 grams of salt per day. However, a typical Indian diet contains about 10-12 grams of salt per day.

Dr Eram Rao, Professor, Department of Food Technology, Bhaskaracharya College of Applied Sciences, University of Delhi, said, “This stark contrast makes us realise that there is an urgent need to redefine our dietary sodium intake habits to healthier standards. This is where MSG offers a promising solution. What makes MSG different is that it has much lower sodium content compared to table salt.”

Poor diet is now the leading cause of death and ill health globally. Of greatest concern is excessive salt intake, with 2 million deaths each year linked to high-salt diets, according to the WHO Global Report on Salt Reduction (2023).

It is estimated that 1.89 million deaths each year are caused by excessive sodium intake, a well-established cause of high blood pressure and increased risk of heart disease.

While table salt contains about 39% sodium, MSG only contains 12%. This means MSG has about one-third the sodium of table salt, yet it still adds that delicious, satisfying flavor to foods due to its umami properties.

By replacing salt with MSG in a dish, sodium levels can be reduced by up to 40%, while the taste of the dish can also be maintained.

With the rising burden of non-communicable diseases such as diabetes, obesity and cardiovascular problems, some of which are closely linked to the modern diet, countries around the world are working on developing strategies to tackle the issue – moving towards adopting low-sodium alternatives.

In 2022, Singapore launched the first-ever national-level strategy to reduce sodium intake by promoting low-sodium salt substitutes such as MSG.

Registered dietitian and health consultant Nilanjana Singh said there have been studies that show excessive amounts of liquid MSG can cause headaches, but adding it to food reduces its consumption.

“MSG is a well-studied food additive that is recognized as safe by leading health organizations. Although some individuals may be sensitive to it, most people can enjoy its umami-enhancing properties without concern,” said Nilanjana Singh.

Dr Rao said that salt is an essential element that brings out the essence of aromatic compounds and plays a vital role in food acceptance, but we must also keep in mind that sodium levels in our body require a delicate balance.

While low salt intake is linked to brain damage, excessive salt intake is linked to high blood pressure.

Given the increasing amount of sodium in the modern diet, controlling sodium intake has become imperative.

Here, substitutes like MSG can play an important role.

“MSG itself is limiting. When food is prepared with less salt and MSG, not only is the taste of the food intact, but sodium consumption is also reduced,” said Dr Rao.

Understanding the science behind MSG can help dispel myths and make informed dietary choices.