Glutamate is considered a migraine trigger, though. Many people do avoid or limit those foods for that reason. Thankfully it doesn’t appear to be a trigger for me, because I love all those things.

There is some controversy about dietary glutamate being directly responsible for migraine. It’s common in the brain already. It’s only allowed selectively through the blood-brain barrier. However it could trigger other types of headache, and those can trigger migraines. Also, apparently more of it is formed in the brain when there are high levels of lysine and ornithine in the body. Many of the foods with high levels of glutamate also have high levels of those aminos.

High levels or low levels of sodium in the body can also be a migraine trigger. MSG is lower in sodium than table salt, but it is additional sodium. Many of the issues blamed on it though are after eating foods that contain MSG and a high amount of salt as well. That’s also true of many of the glutamate-containing foods for that matter (gravies, miso, soy sauce, aged meats).

Doctors recommend eliminating one single ingredient at a time to find your triggers. However, I’m sure many people don’t control for salt when eliminating MSG or natural food glutamate.

> This is definitely not true. There is no biological pathway that can do this

Nevertheless, it continues to give her migraines even in small portions where other foods don't. I don't doubt it could be some byproduct from the process of MSG salt's synthesis or cooking with it rather than the actual glutamic acid, or some allergy as others have suggested.

I wouldn't be so strong as to categorically say that MSG can't cause migraines in any of the human race as you so claim though. There's so much we don't know about human biological mechanisms in niche cases; even water can cause allergic reactions in certain individuals (see Aquagenic Urticaria). What is true generally is not always true specifically when it comes to human health.

MSG is the salt form, wherre the glutamate is bound to a sodium atom. In food, my understanding is that MSG will split into two things: sodium ion and glutamate ion. The difference between adding MSG to food and food being already high in glutamate would be the salt content.

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).

That's very interesting because cheese, paneer and cured meats do trigger wife's migraines. I had not considered that richness is n glutamic acid is a common factor.

The personal, anecdotal relation seems strong on the cheese and paneer component. Even if she had something not aware that it contains either of those it would trigger a migraine, sometimes not immediately though, seems to take a few to several hours.

Will have to try a blind testing with MSG.

For some people, migraines can be triggered by things like light or certain smells. It's not at all impossible that a certain taste can also trigger them.

Migraines are complicated enough that I'd buy a psychosomatic trigger, maybe?