Is Ajinomoto (MSG) Really Bad For You?
By Thiyashi Koththigoda
‘Ajinomoto’ is thought to be bad for you. Used liberally in a Chinese takeaway and processed foods, Ajinomoto or MSG adds that extra savoury flavour. It’s widely believed that this flavour enhancer has negative health effects. But is that really true?
What is MSG?
What we know as Ajinomoto or MSG is a compound called monosodium glutamate. Glutamate is a naturally occurring amino acid found in many foods. These foods include cheese, meat and sardines. Foods like tomatoes, mushrooms and soy sauce are especially jampacked with glutamate. Glutamic acid is also produced in the body since it’s needed for certain functions. When glutamate is isolated and combined with sodium, it creates a stable compound. This powder is monosodium glutamate or MSG. Many of us are familiar with MSG through the term ‘Ajinomoto’. Ajinomoto means ‘essence of taste’ and is the name of the Japanese company that popularised glutamate seasoning.
The company began when Japanese chemist Dr. Kikune Ikeda identified the ‘umami’ taste in kelp broth. Umami is the savoury, meaty flavour that acts as a 5th taste. Dr. Ikeda managed to isolate this flavour and learned that glutamate was behind the taste. Since then, glutamate seasoning has spread worldwide. MSG is usually found in lots of processed, canned and snack foods. It’s included as a food additive under the number of ‘E621’. To produce MSG, starches like sugar cane and molasses are fermented. The processes may be different but there’s virtually no difference between glutamate that’s produced either synthetically or naturally.
Why is MSG seen as bad?
MSG gets a bad rep, even when there are no valid studies that link it to negative health effects. So, where did its controversial nature come from? Many point to an event that happened back in 1968. A physician wrote a letter to the New England Journal of Medicine with some accusations towards MSG. He reported that he was experiencing symptoms like nausea and chest pressure.
He claimed that it was from the Chinese food he ate and attributed it to the MSG in the food. This very letter would lead to MSG sensitivity being labelled as ‘Chinese Restaurant Syndrome’ for years to come. The next year, a study done on the effects of MSG on newborn mice would only go on to cement the negative reputation of the seasoning.
The mice in this study experienced brain damage from the high doses of MSG but these results do not apply to humans. This is because the doses were not reflective of the actual human intake of MSG. It was also later noted that newborn mice were very sensitive to glutamate, making them ill-fitting test subjects. Following these two events, MSG’s effect on the body was still heavily debated.
Many believed that glutamate was an excitatory neurotransmitter, where nerve cells are stimulated to relay a signal in the brain. When in excess, it’s believed to be destructive to nerve cells, making it an excitotoxin. Here again, no valid studies exist to prove that wglutamate acts this way. What has been proven is that dietary glutamate has little to no effect on the brain. Large amounts of MSG can raise blood levels of glutamate, but it’s rarely harmful.
Is There A Valid Case Against MSG?
However, some legitimate concern should be given to those who may actually be sensitive to MSG. People often report feeling symptoms of headache, nausea, numbness and chest pain after eating food with MSG. These short-term negative reactions are part of a glutamate sensitivity known as MSG Symptom Complex. The condition is also synonymous with the term Chinese Restaurant Syndrome. It’s believed that sensitivities happen when trace amounts of glutamic acid cross the blood-brain barrier, causing brain swelling. Studies done on MSG Symptom Complex are also not the most valid. Usually, the doses of MSG given to participants are higher than the daily intake.
A majority of the time, placebo tests were done on those who were self-diagnosed with MSG sensitivity yielded no conclusive results. In terms of the metabolism of MSG, studies have proven that man-made glutamate compounds broke down identically to their natural counterpart. Glutamate is also remarkably low on toxicity. One study found that 15 to 18 g of MSG could be given to a rat per kilogram of its body weight before it showed any risk of dying. Overall, MSG is considered to be safe for consumption by leading world health organisations. This includes the World Health Organisation and the United Nations Food and Agricultural Organisation.
So, what’s the verdict? Should MSG be completely barred out of your diet? Since no concrete proof exists linking MSG to harmful health effects, you can enjoy your Chinese takeaway or packet of chips without a worry. MSG is highest in processed and low-quality foods. If you’re maintaining a healthy diet with whole foods, occasionally having some foods with MSG flavour enhancer added shouldn’t be a big deal.