The MSG-reaction is a reaction to free glutamic acid that occurs in food as a consequence of manufacture. MSG-sensitive people do not react to protein (which contains bound glutamic acid) or any of the minute amounts of free glutamic acid that might be found in unadulterated, unfermented, food.

These ALWAYS contain MSG

Glutamate
Glutamic acid
Gelatin

Monosodium glutamate
Calcium [...]

According to a University of North Carolina at Chapel Hill School of Public Health study, folks who use monosodium glutamate, or MSG, as a flavor enhancer in their food are more likely than people who don’t use it to be overweight or obese. This is the case even when they have the same amount of [...]