Please don't perpetuate the myth of the MSG placebo effect here. It's a cultural meme with no basis in science [1, 2]; glutamate is widespread [3], yet nobody complains of "green tea headaches".

[1]http://www.sciencedirect.com/science/article/pii/02786915939...

[2] http://onlinelibrary.wiley.com/doi/10.1111/j.1745-7599.2006....

[3] http://en.wikipedia.org/wiki/Glutamic_acid_%28flavor%29#Conc...