Joe Biden's former brain surgeon explains why he's not too old to be president

At age 76, former Vice President Joe Biden would be the oldest president to take office if he became the Democratic nominee and won the 2020 election.

Despite his current status as the frontrunner in the race, Biden's age and gaffe-prone tendency have raised some questions as to whether he could be too old to be president.

The neurosurgeon who treated Biden for brain aneurysms in 1988 recently told Politico that “Biden is every bit as sharp as he was 31 years ago” and “he had no brain damage” from the surgeries.

“I am going to vote for the candidate who I am absolutely certain has a brain that is functioning. And that narrows it down exactly to one,” Kassell said.

Other medical experts told Politico that age is a poor metric on its own to determine someone's mental capabilities.

At age 76, former Vice President Joe Biden would be the oldest president to take office if he became the Democratic nominee and won the 2020 election.

Despite his current status as the frontrunner in the race, Biden's age has raised some questions as to whether he could be too old to be president, the subject of recent long-form pieces in The Atlantic and Politico Magazine.

A series of unfortunate missteps and gaffes over the course of his campaign have fed into the narrative that Biden could be too old to take on the full responsibilities of being president, but medical experts and a surgeon who treated him say Biden's gaffe-prone tendency is not a reflection of his mental sharpness.

Before his first presidential run in 1988, Biden underwent successful surgery for two brain aneurysms. His surgeon, Dr. Paul Kassell, recently told Politico's Marc Caputo that the surgeries did not negatively affect his mental capabilities or agility.

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“He is every bit as sharp as he was 31 years ago. I haven't seen any change,” Kassell told the outlet, adding, “I can tell you with absolute certainty that he had no brain damage, either from the hemorrhage or from the operations that he had. There was no damage whatsoever.”

Biden and his fellow Democratic contenders Sens. Bernie Sanders and Elizabeth Warren would all be the oldest presidents in US history, taking office at ages 78, 79, and 71, respectively.

President Donald Trump, who currently holds the record of oldest US president on Inauguration Day, was 70 years and 220 days old upon taking office.

Kassell gave his ringing endorsement to Biden's capabilities, saying, “I am going to vote for the candidate who I am absolutely certain has a brain that is functioning. And that narrows it down exactly to one.”

Kassell and other medical experts on aging told the outlet that concerns over those candidates' ages were exaggerated.

Researcher Dr. S. Jay Olshansky, who led a recent study finding that those candidates are not more likely to die in office because of their age, pointed out that due to their relative wealth and high status in society, prominent politicians are more likely to be healthier and have better access to healthcare.

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“They all belong to a sub-group of the population that is privileged. And privileged sub-groups tend to live longer and better than the average,” Olshansky told Politico, categorizing them as “super-agers,” or individuals in their 70s and 80s who have the mental capabilities of people decades younger.

Another neuroscientist who studies aging, Northwestern University's Emily Rogalski, explained to Politico that scientifically, it's hard to “determine someone's cognitive abilities simply by knowing someone's chronological age.”

Olshansky encouraged observers to cut Biden and the other candidates “some slack” over any mistakes they may make on the trail, saying, “If you've ever given a speech, it's not easy standing in front of a crowd of people ... and avoiding verbal mistakes.”