Does having a PhD make me a better candidate for medical school?

I have a 3.45 GPA BA(Hons.) in psychology and am finishing a PhD in psychology. I want to apply to medical school. I haven't yet taken the MCAT, but I usually score pretty highly on standardised tests. Would having a PhD give me an edge? My research is primarily on healthcare interactions, substance abuse prevention, and training providers. I also have done patient advocacy type work.