I have noticed a trend. People that use their real photographs on their profiles gain the most negative attention and end up having to block people. I have been a member of this site for nearly 4 years, a staff member for more than half that time, and I have never once had anyone pm me anything sexual. My profile picture has also never changed. My photos are only seen by a few select people I have known for years.
Please, if you do not like the attention, do not put up your image on your profile. Find a nice public image that is not under copyright.