(CHICAGO) -- When President Obama celebrated his 50th birthday this year, there were the inevitable comments about how much he's aged only three years into his presidency. The common assumption has always been that presidents age faster while in office -- and die younger as a result.
Now, a University of Illinois researcher has found that many U.S. presidents actually live longer than their peers. In fact, 23 of 34 former presidents who died of natural causes lived several years longer than expected. Among recent presidents, Ronald Reagan and Gerald Ford were both 93 when they died. Jimmy Carter and George H. W. Bush are both alive and well at 87.
There's no doubt that presidents appear to age faster while serving in office -- but graying hair and wrinkling of skin are normal for men their age. And, as the researcher, Jay Olshansky, notes, "We don't die of gray hair and wrinkles."
There are some advantages most presidents have that contribute to a longer life: They're usually college educated, wealthy and have the best medical care available.
So it should come as no surprise that of the last eight presidents, seven lived longer than expected. The exception -- Lyndon Johnson who died of a heart attack at 64.
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