Fox News contributor Marc Siegel joined 'America's Newsroom' to discuss the results of Biden's latest physical as some Americans worry he may not be sharp enough mentally to continue serving.

How old is too old to be president? The current race has brought this question front and center into the national debate. Unfortunately, despite the fact that one candidate is 77 and the other is 81, we still don't have an answer.

One of the reasons we don't know for certain is that modern technology, medication, and an increase awareness of the importance of exercise, sleep, and good diet have increased what is known as healthspan, meaning an older person can stay healthier and functional longer.

Whatever you thought of President Joe Biden’s State of the Union speech this week, whether you admired his sudden energy and vitality and cohesiveness, or whether you were struck instead by his anger, it still didn't directly answer the age question which remained on everyone's mind.

BIDEN'S STATE OF THE UNION SPEECH ANSWERED ONE BIG QUESTION

Is he too old to lead? Is former President Donald Trump? Even neurologists are debating the question. Some feel that as we age, experience and wisdom may........

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