As he barnstorms across Iowa in search of votes this week, Vermont Sen. Bernie Sanders was seeking to allay any concern about his health by releasing a letter from the attending physician of the United States Congress.
The summary, from Dr. Brian Monahan, described Sanders as in "overall very good health," with no history of cardiovascular disease, normal blood pressure and vital signs, and no significant chronic condition.
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"Thank God, I'm in very good health," Sanders told NBC's Lester Holt.
Aside from acid reflux that triggers laryngitis from time to time, and a couple of hernia repairs, Monahan suggested the 2016 presidential candidate is good to go.
At the University of Vermont College of Medicine, Dr. Ben Littenberg, a professor and primary care physician, confirmed the diagnosis.
"He's a remarkably healthy 74-year-old man," Littenberg said after analyzing the letter and summary from Monahan. "(Sanders') medical history shows a few routine problems many people his age have but there's not anything especially threatening to his longevity and nothing too concerning here."
If Sanders were to win the Democratic nomination and go on to win the general election, he would be 75 years old on inauguration day, the oldest person ever to become president.
By contrast, President Ronald Reagan was a couple of weeks shy of 70 years old when he was sworn into office in 1981.
How long might Sanders expect to live?
"He could live a very long time," Littenberg said. "For any one individual it's extremely hard to predict -- he could get hit by a truck -- but on average if you take everybody who is a 74 year old man in America, you live about 12 (more) years."
That population, however, includes men with cancer, heart disease and a range of other serious health risks.
"So, a very healthy 74-year-old man like Bernie Sanders is on average going to live a lot longer than 12 years," Littenberg said.
Even if under the the daily stress and rigors associated with being the leader of the free world?
"It's not clear if that shortens anyone's lifespan," Littenberg said. "It seems to hurt your facial appearance a bit, and hair color, but I don't know that it shortens your life."