Matt Holliday has stopped taking supplements entirely. ?I think it?s my responsibility as an athlete to know what I?m putting in it,? Holliday said. ?I?m not willing to take risks if I don?t know if it?s been approve by the ? players association. I quit taking supplements all together. I?ll stick to a protein shake and that?s about it. I don?t think that?s an area that I would ever take a chance not knowing.?