Donald Trump is sharp, but needs to lose weight: White House doctor

US President Donald Trump passed a cognitive test and is in overall excellent health, but needs to lose 10 to 15 pounds (4.5 to 6.8 kg) by eating better and starting to exercise, the White House physician said on Tuesday.

Trump, seeking to put to rest lingering questions about his mental fitness for office, asked his doctor to add a cognitive screening test to his first presidential medical exam - and  also authorized Dr. Ronny Jackson to release a battery of data from the tests.

The Navy doctor exhausted reporters' questions during an unusually lengthy hour-long session, at Trump's request, and said he did not withhold any information in the interests of privacy.

"He said, 'I want you to get out there and I want you to talk to them and I want you to answer every single question they have,'" Jackson said of Trump.

Trump, 71, is known to enjoy high-fat foods like fried chicken, hamburgers and steak - and while he plays golf, he does not have a daily exercise routine.

Trump's mental fitness for the job had come under intense scrutiny after a controversial, best-selling book, "Fire and Fury: Inside the Trump White House," portrayed him as childlike and mercurial.

Past presidents are not known to have been tested for mental acuity while in office - including Ronald Reagan, who five years after leaving the White House was diagnosed with Alzheimer's disease.

Jackson, who speaks with Trump a few times a day and travels with him, said he did not think the president needed cognitive testing based on medical guidelines - but added the 30-question Montreal Cognitive Assessment at Trump's request.

The test looks for signs of dementia or Alzheimer's, an incurable, degenerative brain disease. Sample questions include asking the patient to draw a clockface, putting in all of the numbers and setting the clock hands to a specific time. The test does not assess psychiatric fitness.

Trump scored 30 out of 30 on the test, Jackson said. "The president is mentally very sharp, very intact," he said.

Dr. Ronald Petersen, an Alzheimer's disease expert at the prestigious Mayo Clinic, said he could not comment specifically on the president's cognitive health. However, he did say that, in theory, a perfect score on the Montreal Cognitive Assessment does not necessarily rule out cognitive decline. It is "just one measure in a clinical judgment," he said in an email.

Trump underwent the medical exam on Friday at Walter Reed National Medical Center.

Trump is considered overweight and borderline obese at 6 feet 3 inches (1.9 meters) tall and 239 pounds (108 kg). His blood pressure was 122/74, within normal bounds, and his cholesterol was on the high side.

Jackson said he would increase Trump's daily dose of Crestor, a cholesterol drug, and bring in a nutritionist to work with White House chefs. The doctor also said he would also design a daily exercise program for Trump.

"He's more enthusiastic about the diet part than the exercise part, but we're going to do both," Jackson said, adding that he might enlist first lady Melania Trump to help.