Questions about Hillary Clinton's health have dominated headlines for the past 24 hours but concerns about the physical and mental health of presidential candidates -- individuals with high-stress day jobs who tend to be older -- are nothing new.
Jacob Appel, an assistant professor at Mt. Sinai Medical School who has studied the history of candidates' health, said there was no real expectation for presidents or wannabes to reveal information until 1955, when President Eisenhower had a heart attack and allowed his doctor to speak to the public about it.
Since then, Americans expect to know if their potential presidents are up for the demanding job. Most candidates have some kind of issue in their medical history and most err on the side of withholding information.
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For instance, Bob Dole, John Kerry and John McCain were all cancer survivors who had been wounded in combat. All three are still active: Kerry is secretary of state, McCain is running for reelection in the Senate in Arizona, and Dole, at 93, attended the Republican National Convention and still gives interviews.
"The vast majority of people in their 50s, 60s, and 70s have a long laundry list of illnesses that might affect them every day, but are perfectly fit people" to do their jobs, noted Appel. "You want to ask yourself not if a candidate has an illness, but if they have an illness that would impair their ability to serve out their term or to govern effectively."