I understand why you want to avoid the carbs, but what is it about MSG that makes you try to avoid it? I ask only because glutamate occurs naturally in just about every protein and the average person consumes at least ten times more glutamate from these natural sources than they do from "added" sources. Your body stores about four pounds of glutamate in your brain, muscles and organs at any given time. Your body also creates about 50 mg. of glutamate each day. I don't know what you'd live on if you were really trying to eliminate MSG from your diet.
MSG and natural glutamate are not the same thing.
Well, MSG wasn't even invented until 1908, so it isn't a food with a millenia-long record behind it. It's the same reason I don't trust Canola oil: anything that has to be processed that much to make it "edible" really isn't edible.