There was a Japanese study about this awhile back and that was the general conclusion; that the signaling is important regardless of any "real" effect. https://

There was a Japanese study about this awhile back and that was the general conclusion; that the signaling is important regardless of any "real" effect. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3536629/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3536629/