Which Side Is Your Good Side? Here Comes the Science:

scienceandstuff:

Whatever you do, accentuate that left cheek of yours: it is your best one. According to a scientific study, there no longer remains a question of which is your best side. Everyone, it seems, agrees that left is best.

Wake Forest University psychology professor Dr. James Schirillo and co-author Kelsey Blackburn published their findings in the journal Experimental Brain Research, stating that we humans prefer looking at the left side of a face, finding it more pleasant.