Trump, in the interview published Thursday, said he regretted undergoing the advanced imaging on his heart and abdomen during an October visit to Walter Reed National Military Medical Center because it raised public questions about his health. His physician said in a memo the White House released in December that he had “advanced imaging” as a preventative screening for a man his age.

Trump had initially described it as an MRI but said he didn’t know what part of his body he had scanned. A CT scan is a quicker form of diagnostic imaging than an MRI but offers less detail about differences in tissue.

The president’s doctor, Navy Capt. Sean Barbabella, said in a statement released Thursday by the White House that Trump underwent the exam in October because he planned to be at Walter Reed to meet people working there. Trump had already undergone an annual physical in April.

“President Trump agreed to meet with the staff and soldiers at Walter Reed Medical Hospital in October. In order to make the most of the President’s time at the hospital, we recommended he undergo another routine physical evaluation to ensure continued optimal health,” Barbabella said.

Barbabella said he asked the president to undergo either a CT scan or MRI “to definitively rule out any cardiovascular issues” and the results were “perfectly normal and revealed absolutely no abnormalities.”

White House press secretary Karoline Leavitt said in a statement Thursday that the president’s doctors and the White House have “always maintained the President received advanced imaging” but said that “additional details on the imaging have been disclosed by the President himself” because he “has nothing to hide.”

“In retrospect, it’s too bad I took it because it gave them a little ammunition,” Trump said in the interview with The Wall Street Journal. “I would have been a lot better off if they didn’t, because the fact that I took it said, ‘Oh gee, is something wrong?’ Well, nothing’s wrong.”

The 79-year-old became the oldest person to take the oath of office when he was sworn in as president last year and has been sensitive to questions about his health, particularly as he has repeatedly questioned his predecessor Joe Biden’s fitness for office.

Biden, who turned 82 in the last year of his presidency, was dogged by scrutiny of his age and mental acuity at the end of his tenure and during his abandoned attempt to seek reelection.

But questions have also swirled around Trump’s health this year as he’s been seen with bruising on the back of his right hand that has been conspicuous despite a slathering of makeup on top, along with noticeable swelling at his ankles.

The White House this summer said the president had been diagnosed with chronic venous insufficiency, a common condition among older adults. The condition happens when veins in the legs can’t properly carry blood back to the heart and it pools in the lower legs.

In the interview, Trump said he briefly tried wearing compression socks to address the swelling but stopped because he didn’t like them.

The bruising on Trump’s hand, according to Leavitt, is from “frequent handshaking and the use of aspirin,” which Trump takes regularly to reduce the risk of heart attack and stroke.

He said he takes more aspirin than his doctors recommend but said he has resisted taking less because he’s been taking it for 25 years and said he is “a little superstitious.” Trump takes 325 milligrams of aspirin daily, according to Barbabella.

“They say aspirin is good for thinning out the blood, and I don’t want thick blood pouring through my heart,” Trump said. “I want nice, thin blood pouring through my heart. Does that make sense?”

Trump, in the interview, denied he has fallen asleep during White House meetings when cameras have caught him with his eyes closed, instead insisting he was resting his eyes or blinking.

“I’ll just close. It’s very relaxing to me,” he said. “Sometimes they’ll take a picture of me blinking, blinking, and they’ll catch me with the blink.”

He said that he’s never slept much at night, a habit he also described during his first term, and said he starts his day early in the White House residence before moving to the Oval Office around 10 a.m. and working until 7 p.m. or 8 p.m.

The president dismissed questions about his hearing, saying he only struggled to hear “when there’s a lot of people talking,” and said he has plenty of energy, which he credited to his genes.

“Genetics are very important,” he said. “And I have very good genetics.”