MSG Facts

In 1908 a Japanese scientist discovered an active ingredient in seaweed could be used to greatly enhance the flavour of foods. Since then, the sodium salt monosodium glutamate (MSG, 621), isolated from glutamic acid in kombu, was used to flavour foods in Japan. The world-wide use of processed free glutamic acid soon exploded.

MSG is one of the most widely used food chemical additives in the world. Back in the 1960s, 262,000 tons of MSG was manufactured but today more than 800,000 tons are produced.

What is MSG?

MSG is a natural building block of proteins and when it’s not attached to protein it enhances the flavour of foods. However, consumption of MSG can cause a vast range of side-effects including eczema symptoms. The first medical reports on the adverse effects of MSG referred to it as “Chinese Restaurant Syndrome”.

MSG is a flavour enhancer that is natural (for example, it is naturally present in tomato) and it’s also artificial with a nature-identical versions added to foods such as savoury biscuits, canned soups, meat marinades and seasonings.

How MSG affects the brain

According to the American Nutrition Association, manufactured free glutamic acid and other forms of MSG, including hydrolyzed vegetable proteins, are added to processed foods to mask ‘off’ flavours. MSG basically makes the blandest and cheapest foods taste good. How does it work? Glutamic acid is a neurotransmitter that excites neurons in our brain (not just in our tongues). This electrical charging of neurons is what makes MSG-laden foods taste wonderful. The next time you eat MSG-rich foods, notice how you feel a few seconds afterwards. Unfortunately, our brains have many receptors for glutamic acid and some areas, such as the hypothalamus, do not have an impermeable blood-brain barrier, so free glutamic acid from food sources can enter the brain and sometimes damage the brain and kill neurons, according to the American Nutrition Association.

Low MSG doses can be problematic

American researchers tested how people react to MSG on an empty stomach (which is commonly when we eat). The subjects, who were mostly medical students and doctors, were fed soups with increasing doses of MSG and half of them reacted to low doses between 1.5 and 4 grams, and most of the remaining people reacted to doses between 5 and 12 grams, which are the amounts found in some packaged snack foods and takeaway meals. One 25 gram serve of protein powder contains about 4 gram of glutamic acid, which is a type of MSG.

Eczema, MSG and chemical sensitivity: the facts

  • More than 90% of people with eczema have chemical sensitivities and 35% of people with eczema have adverse reactions to MSG (research by Loblay and Swain, RPA Hospital in Sydney). More about eczema and MSG sensitivity can be found here
  • In animal studies, MSG ingestion caused liver inflammation and significantly increased the size of the liver, promoting liver damage.
  • According to a Japanese study published in the Journal of Dermatology, consuming soy sauce*, fermented soybeans*, chocolate^, cheese^, coffee^ and yoghurt^ causes a worsening of eczema symptoms. After the avoidance of these foods for three months 100% of the participating eczema sufferers had reduced eczema symptoms. (*Products containing MSG, ^Products containing other problematic food chemicals)
  • 36 healthy people were fed increasing doses of MSG and everyone suffered various adverse symptoms including burning sensations, irregular heartbeat and headaches. Some of the participants had adverse reactions to as little as 3 grams of MSG while others could tolerate up to 21 grams before they experienced unpleasant side-effects.

Fischer, K., 2014, ‘MSG Facts', Eczema resources and articles,


Eczema and MSG Sensitivity