It ain't easy being the leader of the free world. This is true on the face of the President of the United States of America Barack Obama and all the previous Presidents as well. Once you land the gig of head American honcho, the hair starts going gray, the wrinkles start getting deeper and life looks like it has squashed itself on your once GQ-worthy face.
The Washington Post had an excellent sliding picture that showed the aging of Obama over a presidential term but if you want to get a real feel of the shift, this super fast slideshow/timelapse by Jeremy Tubbs for Presidial.org reveals all you need to know. Tubbs stitched together over 2,500 pictures of Obama over the past 5 years. From January 1st 2008 to December 31st 2012. It's like twice the years in half the time. [Presidial, Jeremy Tubbs via TDW]