Before-and-after photos show how dramatically presidents aged in office

• Americans took notice of the expedited presidential aging process known to plague commanders-in-chief.

• Over the last 50 years, signs of aging have grown more noticeable as presidents are constantly photographed.

• Side-by-side photographs capture presidents' changing faces from inauguration to their last day in the White House.

As President Barack Obama reflected on his time in office, he had a way of acknowledging his waning time in the position: a joke about his graying hair.

"Right now, we are waging war under authorities provided by Congress over 15 years ago — 15 years ago," he said in December 2016.

"I had no gray hair 15 years ago."

Indeed, despite his close-cut hairstyle, it was impossible not to notice the trademark presidential graying, as the president's short black hair became more of a salt-and-pepper color.

In later appearances, like an endorsement video for his former Vice President Joe Biden on Tuesday, the former commander-in-chief was noticeably gray.

Though some dermatologists maintain presidents are victims of an expedited presidential aging process, appearing to age faster because of the stress of the office, others say it's more attributable to natural aging than stress.

Other studies, including a comprehensive analysis of elections dating back to the 1700s, have found that heading a nation can take years off a leader's life. That analysis, from the Harvard Medical School, found that elected heads of government, on average, have lives almost three years shorter than those of the candidates they defeat.

Here's how past US presidents have looked near the beginnings and ends of their respective terms:

President Joe Biden took on the mantle as the oldest president to take office at 78 years old when he was inaugurated on January 20, 2021.

Biden, now 79, has not visibly aged much after being in the White House for just under two years thus far.

But the president has had his hands full as the US balances on the cusp of an economic downturn ahead of contentious midterm elections.

Donald Trump was 70 when he took office, the oldest in history at the time.

Source: AP

Now 76, he doesn't look much different.

By his last year in office, Trump didn't seem to display the traditional appearance of aging. However, that could be due to his penchant for wearing makeup to appear healthy and robust.

In a year where he faced the coronavirus pandemic and a tense bid for reelection, many noticed he had faded in his own ways, with his usual orange hair faded to white, and his hands pale in stark contrast to his orange face.

Now the former president is embroiled in a myriad of legal issues centering on his alleged efforts to overturn the 2020 election, accusations of criminal tax fraud at the Trump Organization, and an investigation into classified documents found at his Mar-a-Lago residence.

Obama looked youthful when he took the oath of office on Inauguration Day, January 20, 2009.

By his year-end 2016 news conference at the White House, he was weathered.

Here's George W. Bush making a phone call shortly after the 2000 election.

And here's Bush fielding questions during his final White House press briefing, on January 12, 2009.

Hillary Clinton and Bill Clinton looked energetic at a dinner in 1993 several days before his first inauguration.

Here's Clinton giving a brief speech toward the end of his term in October 2000.

Appearing without his trademark glasses, then-Vice President George H.W. Bush answered a question at the second presidential debate in October 1988.

By June 1992, as Bush addressed a crowd of veterans during a ceremony at the Korean War Memorial, several months before losing the presidential election, he looked older.

Former President Ronald Reagan and first lady Nancy Reagan greeted fans lined up in Washington at his first inauguration in January 1981. Though he was 69, his movie star appearance held up.

When Reagan returned to Washington after his final trip as president to Camp David in January 1989, he looked quite different.

Though the photo is black-and-white, you can see Jimmy Carter emerging from a Georgia voting booth on Election Day in November 1976.

Here's Carter preparing for his farewell address to the nation in January 1981.

President Richard Nixon gave a press conference in the East Room of the White House several weeks after being sworn in in 1969.

Plagued by the Watergate scandal, a glassy-eyed Nixon delivered a final speech for White House staff and members of his Cabinet in 1974.

President Lyndon Johnson proclaimed a day of mourning for deceased President John F. Kennedy shortly after being sworn in in 1963.

Johnson, who didn't visibly age too much in his five-year tenure, joins Nixon shortly after Nixon is elected president in November 1968.

Editor's note: This list was first published in December 2016 and has been updated to reflect recent developments.

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