Here's What These Presidents Looked Like Before and After Serving in Office

It's no secret that being the president of the United States is one of the most stressful jobs a person can have. A study published in the British Medical Journal in December 2015 suggests that being elected to public office may actually lead to accelerated aging due to the stress of the job. In other words, it's not too surprising to notice presidents developing gray hairs and wrinkles after just a few years in office. We've rounded up photos of 21 former U.S. presidents, from William McKinley to Donald Trump, to compare how they looked before and after their terms.

Some presidents have turned to exercise and other hobbies to manage the stress of the job. Barack Obama shared on social media that he de-stressed by taking a short walk outside between the Oval Office and the residence. John Quincy Adams was known to start every day with either a two-mile walk or swim in the Potomac River. Dwight D. Eisenhower regularly found time in his schedule to paint as a form of relaxation. Presidents: They're just like us!

We've also included a few notable events or interesting facts about each U.S. president along with their photos. And if you're curious about some of the other famous White House occupants, we've got some of the rules you didn't know first ladies have to follow and insight on what life in the White House is like for the children of presidents.