A head of white hair is striking and elegant. Yellowed white hair, however, looks dull and dirty. White hair turns yellow due to a number of factors, some of which you can control -- such as smoking -- and others that you can't. White hair is white simply because it lacks any pigment whatsoever -- and sometimes, those pigmentless hair strands pick up stains and colors from their surrounding environment. The best way to eliminate yellow from your crown of white, then, is to either remove the foreign substances or add a balancing tint to correct the color back to snowy perfection.