How presidents have aged while in office

POSTED: 08:20 PM PDT Sep 24, 2012    UPDATED: 08:16 AM PDT Aug 04, 2016 
President Barack Obama, Jan. 17, 2016

There's a saying that presidents age twice as fast while in office. With Thursday marking President Barack Obama's 55th birthday, take a look back over the past 60 years of U.S. presidents and judge for yourself how much the office aged them.