Lack of rest, dehydration, poor diet, and exposure to throngs of strangers is a recipe for illness.

Imagine you’ve been traveling from state to state to state.

You’re not getting enough sleep, and maybe you’re not eating the healthiest of foods.

You’re also shaking hands with hundreds of strangers, making yourself vulnerable to any illnesses they might have.

Now, say you’ve been doing that for months under stressful conditions.

If you were, then you’d be leading a life like presidential candidates Hillary Clinton and Donald Trump.

The health of the two contenders for the White House has come under scrutiny this week after Clinton was diagnosed with pneumonia, and both candidates released medical records.

In this fall’s presidential race, both candidates are expected to have busy campaign schedules.

That would wear down most people, not to mention a 68-year-old woman and a 70-year-old man.

“It would take a physical toll on anybody,” Dr. Randy Wexler, M.P.H., F.A.A.F.P., associate professor of family medicine at The Ohio State University, told Healthline. “It places a stress on the body and when the body is under stress it compromises the immune system.”

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A presidential campaign is almost a perfect incubator for illness.

Wexler said the most important component is lack of sleep — not getting enough hours of sleep and not getting uninterrupted and truly restful sleep.

He said dehydration is another big factor. Busy candidates may not even realize they are in hydration trouble.

“By the time you’re thirsty, you can already be dehydrated,” he said.

He added candidates also tend to eat a lot of fatty food on the campaign trail and end up shaking hands with a lot of people, many of whom may have contagious illnesses.

Given all that, it perhaps shouldn’t be surprising that Clinton came down with what is commonly referred to as “walking pneumonia.”

Wexler said most cases of this illness aren’t serious enough for hospitalization. He said rest and antibiotics usually take care of the major symptoms.

“It’s potentially serious, but it’s just an inconvenience for most people,” he said.

As for Clinton feeling lightheaded at Sunday’s Sept. 11 memorial event, Wexler said that can easily happen to someone with an illness in a crowded area where body temperatures naturally rise.

Indeed, it happened to President George H. W. Bush at a state dinner in Japan in 1992.

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These health concerns prompted both candidates to release recent medical records this week.

Clinton made her medical records public on Wednesday. She had released other information in July.

The Democratic nominee’s records show her blood pressure is 100/70 and her heart rate is 70. Her doctor said Clinton’s lab results were normal and she was “quite healthy” overall.

Trump released his medical records on Thursday, the day after he discussed them during a taping of “The Dr. Oz Show.”

The Republican nominee’s records stated he stands 6 feet 3 inches tall and weighs 236 pounds. It added he has normal blood pressure and cholesterol levels.

Campaign officials said the results show Trump is in “excellent health.”

Wexler said the main things people should look for in a candidate’s medical records are blood pressure and vital signs as well as cholesterol and blood glucose levels.

He added he also would like to know what medications a candidate is taking.

“I’d want to know if their tests are normal because they are taking medication or because they have no underlying health issues,” Wexler said.

He said past history of smoking and alcohol use are also important.

Wexler said he isn’t certain if the public necessarily has the right to know details about a candidate’s health.

After all, most people don’t like to share that information.

“Health information is the most personal information a person has,” he noted.

There’s also a history of presidents and candidates hiding health information. Former President John Kennedy, for example, had Addison’s disease, a fact that was kept from the public while he was in office.

Wexler said such information can help the public gauge a candidate’s fitness for office.

“It certainly is something I think people want to know,” he said.

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