Obama Has Aged A Lot In 8 Years

It's been said that the presidency ages you at an expedited rate, and Barack Obama is living proof of this. The gray-haired, haggard-looking president who graces the airwaves in 2016 is only eight years older than the fresh-faced Illinois senator who assumed the office in 2009, yet the difference is remarkable. These photos show Obama's evolution from eager young man to world-weary president.

According to one doctor who examined the medical records of U.S. presidents dating back to the 1920s, the average president ages two years for every year they're in office. However, a professor who studied the aging of presidents took issue with this assessment, noting that out of the 34 presidents who died from natural causes, 23 lived longer than what was predicted of them at the time of their inaugurations. The first eight presidents lived to an average age of 79.8, far more than the life expectancy of the average man in the early 19th-century.

This medical dispute notwithstanding, being president certainly appears to take a physical toll on those who hold the highest office in the land. Let's take a look at how Obama has aged during his eight years in the oval office — the differences between 2008 and 2016 may be starker than you remember.

America Meets Obama

America was introduced to Obama at the 2004 Democratic National Convention, for which he gave the keynote address.

Running For The Senate

Here's Obama as an Illinois state senator in 2004. Three months, he was elected to the U.S. Senate.

Serving In The Senate

Obama's time in the U.S. Senate was brief, as he was elected to the presidency just four years into his first and presumably only term. Here he is at a confirmation hearing in 2005.

Flip Phone Obama

Obama uses a flip phone at a 2006 White House event.

A Trip To South Africa

Obama meets with Nobel Prize winner Desmond Tutu during a trip to South Africa in 2006. Three years later, Obama himself would win the Nobel Prize.

Running For President

Obama meets with a supporter in 2007, two days after announcing his presidential run.

Meeting The Press

Obama talks to the late Tim Russert about his presidential campaign during a 2007 appearance on Meet The Press.

Hitting The Road

The future president stops by First Brown Chapel AME Church in Selma, Alabama, while campaigning in 2007.

Exit Stage Right

Obama calmly exits after his final presidential debate with Sen. John McCain in 2008.

The New President

Obama waves to the crowd in 2009 at his first inaugural parade.

Pushing For Health Care

President Obama speaks at an AARP town hall event while campaigning for health care reform in 2009.

An Uneasy Relationship

Obama gives a joint press conference with Israeli Prime Minister Benjamin Netanyahu in 2010. The two proceeded to have a tense and sometimes hostile relationship throughout Obama's presidency.

Talking Business

Obama talks about small businesses from the South Lawn of the White House in 2010.

Home For A Visit

In November 2011, three years into his presidency, Obama smiles during a speech in Honolulu.

Running For Reelection

While running for reelection in 2012, Obama looks a tad wearier than the bright-eyed man who ran four years earlier.

Another Health Care Push

In 2013, a gray-haired Obama touts the Affordable Care Act, encouraging Americans to sign up for the landmark health care program.

A Festival of Lights

Obama holds a menorah while giving remarks on the second night of Chanukah in 2013.

An Oval Office Signing

Obama signs the Child Care and Development Block Grant Act in 2014, a law aiming to expand accessibility to and strengthen safety requirements for child care services.

Obama Goes Casual

Obama enjoys some shaved ice during a trip to Hawaii in 2015.

An Eye Toward The Future

Obama attends a Christmas tree lighting ceremony in December 2015.

With less than three months to go before the end of his presidency, Obama is more grizzled, hardened, and weary than the man he was eight years ago — and it shows.