Hi! I actually did a presentation on MSG today.
MSG is a derivative of the amino acid glutamate. Glutamate is widely present in meat and veggies/fruit and is an important component in fermented products like soy sauce of fish sauce. It gives the umami taste. MSG gives the same umami taste.
In animal experiments, it has been observed in juvenile mice/rats that MSG can induce obesity/weight increase. Though, these results can’t be extrapolated to man because these animals were given extremely high doses a person doesn’t consume and the MSG was injected subcutaneously. This resulted in destruction of certain brain regions.
These animal studies are still used as an example why MSG could be dangerous, but they’re not relevant in man. I believe this is why MSG is still seen as potentially harmful, and why people link a headache after eating Chinese food. Also racism.
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