Earlier quoted context omitted.
I have a family member who has discovered through gradual process of elimination that she gets migraines from MSG, aspartame and yeast extract. "just sodium headaches" doesn't really apply to her case; simply chewing a piece of gum that has aspartame, or eating a piece of meat cooked with MSG in her salad is enough to trigger them. I agree in the general sense with your comment and the article that there's no widespr…
> discovered through gradual process of elimination that she gets migraines from MSG This is definitely not true. There is no biological pathway that can do this. MSG is nearly identical to the glutamic acid in other foods. If it were true they'd be unable to tolerate parmesan cheese, soy sauce, aged meats, tomatoes, mushrooms, and seaweed.
I don't recommend telling people their subjective experience isn't true- you don't know for sure that they don't actually get migraines from MSG. I think it's fine to tell people that often their subjective experiences can be colored by prior knowledge, and people often ascribe causes to unrelated factors. (My personal belief is that most people who say they got a headache from MSG experienced a headache, but consuming glutamate was not the cause).