How old is too old to be president?

Photos: U.S. presidents: Ailing in office
John Adams 1797-1801 – A study by Duke psychiatrists found John Adams would have been diagnosed with a bipolar disorder.
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Photos: U.S. presidents: Ailing in office
William Henry Harrison, March-April 1841 – William Henry Harrison battled with dyspepsia and indigestion. Before he had been in office a month, he caught a cold that developed into pneumonia. On April 4, 1841, he became the first president to die while in office.
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Photos: U.S. presidents: Ailing in office
Abraham Lincoln, 1860-1865 – Abraham Lincoln is widely thought to have suffered from depression.
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Photos: U.S. presidents: Ailing in office
Ulysses S. Grant, 1869-1877 – The study by Duke psychiatrists found Ulysses S. Grant would have been diagnosed as an alcoholic with social phobias.
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