[tptacek]

Scientists have been doing challenge studies with MSG for 4 decades, and no study that presented subjects with MSGs and detected any adverse reactions significantly different than placebo has ever reproduced.

Even the (rebutted, non-reproducing) studies that showed adverse reactions to MSG (in the 80s and early 90s) showed headache as one of the symptoms not associated with MSG (tingling and numbness were more closely associated).

I don't doubt you're able to give yourself a migraine, but I do doubt that you're controlling for MSG.

This might be one of the best-studied food safety questions in the literature.

[itbeho]

I think it’s very likely that something with MSG on the label often includes things like anti-caking agents or nitrates that may actually be the culprit. I kept a food diary for a year and the common headache trigger seemed to be “MSG”. Changing my diet to avoid it eliminated the headaches. So it really doesn’t matter to me if someone on the internet says it can’t be MSG. The practical result in my case was close enough. I have sympathy for anyone that suffers from migraines.

[kazinator]

Anti-caking agents are used in powders other than MSG.

[wollstonecraft]

Ajinomoto vs Morton's salt as the control, milled to the same consistency in gelcaps.

How did they find the subjects? Was it a general call for college students, or did they attempt to drill down to find rare sensitive individuals?

[tptacek]

Which study? There are dozens of them.