Sen. Elizabeth Warren, D-Mass., on Friday released a letter from her physician describing her as "very healthy" and issued five pages of supporting medical records, making her the first septuagenarian in the Democratic presidential contest to provide a glimpse at the details of her health.

"There are no medical conditions or health problems that would keep her from fulfilling the duties of the President of the United States," wrote Beverly Woo, a physician at Brigham and Women's Hospital in Boston who has been seeing Warren for two decades.

By releasing her records first, Warren arguably sets a bar for the others in a presidential field that includes four contenders who, if elected, would be the country's oldest president at their first inauguration.

Warren takes medication for hypothyroidism, a common condition in which the thyroid gland is underactive, according to the letter. Her blood pressure is 115/57, and she has had a flu shot this year.

Warren is 5 feet 8 inches tall and weighs 129 pounds. "She exercises regularly and follows a healthy diet despite her very busy schedule," Woo wrote.

In addition to the letter from her physician, which is similar to what most recent presidential candidates have offered, Warren also provided a hematology report including information on everything from her platelet count to the size of her red blood cells.

The health of the presidential candidates has taken on more significance this year because the field is historically old, with four Democratic contenders who are 70 or over. Three of them - Warren, Sen. Bernie Sanders, I-Vt., and former vice president Joe Biden - are polling toward the top of the field.

The nominee will take on President Donald Trump, who holds the record as the oldest man to assume the presidency and is now 73.

Although Trump has had doctors who describe his health in glowing terms, he recently made an unplanned stop at Walter Reed National Military Medical Center for reasons that remain unclear. Trump's doctor described the visit as a "interim checkup."

Sanders, at 78, is the oldest candidate in the race. He suffered a heart attack while campaigning in Las Vegas on Oct. 1, which sidelined him until a Democratic debate two weeks later. Sanders had two stents inserted, but his campaign has declined to specify how much damage his heart sustained and declined interview requests with his physician.

The Vermont senator's campaign has said it would provide his health records by the end of the year. Sanders released a letter in January 2016 - during his last presidential campaign - from Brian Monahan, the attending physician to the U.S. Congress, that described Sanders as having a "mild" case of high cholesterol.

Biden, another top Democratic contender at 77 years old, also has faced persistent questions about his health. The latest came Thursday at a campaign stop in Iowa, when a former farmer confronted him about his age and other topics.

"You're damn near as old as I am," the man said. "You're too old for the job. I'm 83, and I know damn well I don't have the mental faculties I did 30 years ago."

Biden replied, "I'm not sedentary." He added, "And you want to check my shape, man, let's do push-ups together here, man. Let's run. Let's do whatever you want to do. Let's take an IQ test. Okay?"

After a debate in September in which his answers sometimes meandered and one challenger appeared to allude to his age, Biden committed to releasing his health records ahead of the Iowa caucuses on Feb. 3. When asked by reporters the following day about concerns regarding his metal acuity, Biden deflected.

"What the hell concerns?" Biden asked. "Man, you want to wrestle?"

Billionaire and former New York mayor Mike Bloomberg, the most recent candidate to enter the race, is also among the oldest at 77 years old. His campaign has not said if he will release his medical records.

As mayor, he made provisions for healthy living part of his agenda. That includes a so-called soda ban he pushed in New York, intended to prevent restaurants and food service establishments in the city from selling "sugary beverages" in cups larger than 16 ounces.

In contrast, the other contender at the top of the Democratic field, South Bend, Indiana, Mayor Pete Buttigieg, is among the youngest presidential candidates in history at 37.