Elizabeth Warren "is in excellent health," according to a doctor's report released by the Massachusetts senator on Friday, becoming the first in a trio of top Democratic presidential candidates over 70 to make their medical records public.

Warren's last physical was in January and was conducted by Dr. Beverly Woo, who said she has served as the candidate's primary care physician since 1999. Woo wrote in a one-page letter dated this week that Warren's "only medical condition" is an underactive thyroid gland, which is easily treated by medication, the only kind she takes.

The 70-year-old senator had her annual flu shot in October, and a routine mammogram in January found no sign of trouble. At 5 feet, 8 inches, she weighs 129 pounds, exercises regularly and follows a healthy diet, the doctor wrote.

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She has never smoked, misused drugs or had a problem with alcohol.

Woo said Warren's January checkup found no red flags. In fact, her blood pressure was lower than is usual for someone her age — 115 over 57 — and her heart rate was 70, levels that are seen in people who exercise regularly.

"If I were seeing a 70-year-old woman in my clinic with these vital signs, physical exam and lab values, I would tell her that she is quite healthy for her age," said Dr. Brian Antono, a family medicine specialist at Georgetown University School of Medicine who reviewed the health information released by Warren's campaign.

Warren underwent a long list of blood tests at that physical, and none signaled any underlying diseases. Importantly, they indicate she's at low risk of heart disease and stroke. Her blood sugar was normal. Her cholesterol was in the healthy zone, with a total cholesterol of 193 and level of the so-called "bad" subtype, or LDL, at 88.

Her level of HDL, or "good" cholesterol, was an unusually high 95. In contrast to the other cholesterol types where a lower number is better, an HDL higher than 60 is considered protective — and Antono said the thyroid condition Warren has sometimes bumps up that number.

"Her normal cholesterol levels combined with the rest of her 'puzzle pieces' – normal blood pressure, normal blood sugar and non-smoker status – are all positive contributors to an overall reassuring heart health," Antono said.

The senator frequently jogs onto stage at her rallies and says she keeps healthy by walking frequently while talking on the phone or listening to audiobooks, with the goal of doing 7 miles daily. "But I don't always hit it," she says.

Warren is among her party's primary front-runners along with Vermont Senator Bernie Sanders, 78, and former Vice President Joe Biden, 77. Also in the top tier is Mayor Pete Buttigieg of South Bend, Indiana, who is 37.