Media reports have been raising questions about President Donald Trump's health after videos of his graduation speech Saturday at the U.S. Military Academy at West Point, New York, began circulating.

During the speech, Trump began to raise a glass of water to his mouth with his right hand, but appeared to have trouble lifting it further, bringing up his left hand to help.

After the speech ended, he walked slowly and haltingly down a ramp to get off stage, watching his feet the entire time, with an Army general at his side for the whole descent.

That evening, Trump defended himself on Twitter, calling the ramp "very long & steep, had no handrail and, most importantly, was very slippery. The last thing I was going to do is 'fall' for the Fake News to have fun with."

The next day, June 14, Trump turned 74, the oldest any president has been during his first term. His age, combined with limited information on the president's overall health, have led to speculation about whether the episodes point to some larger neurological problem.

Physicians are hesitant to speculate about what that condition, if one exists at all, might be. On CNN, Sanjay Gupta, MD, said it's "so hard to say" if the president has neurological issues just from looking at a video.

"I talked to a bunch of neurologists over the weekend, a lot of people talking about this," Gupta said. "People always have something to say and weigh in on this, but I'll start with the end: there are a lot of clues in there, but no conclusions."

He shared insights into what questions might run through physicians' heads after watching the tape: "Is it balance problems? Is there some weakness there? Is there numbness in the feet, perhaps a type of neuropathy? Is it just a slippery ramp as the president said, or slippery shoes?"

"We don't know and I think you have to be very cautious in trying to determine anything, certainly not diagnose anything or even speculate on this," Gupta said.

Gupta said the fact that Trump was looking down at his feet the entire time struck him "even more than his gait. The gait could be explained by a lot of different things."

Still, he cautioned that it was only a 20-second video: "I think anybody would have a hard time making anything of it."

It's not the first time Trump has struggled with raising a glass of water to his mouth. A January 2018 article in The Atlantic questioned whether Trump has any cognitive or neurological issues, citing an episode the previous November in which Trump used his left hand to steady a bottle of water as he was drinking it; and in another appearance the next month, he grabbed a glass of water with both hands and held it like that for the entire sip.

That same month, December 2017, Trump slurred his words during a speech on relocating the American embassy in Israel from Tel Aviv to Jerusalem.

More recently, in November 2019, Trump made an unscheduled visit to Walter Reed National Military Medical Center, but his aides dismissed it as part of a routine annual physical that included lab work.

In an unusual late-night memo at the time, White House physician Cmdr. Sean Conley, MD, wrote that "[d]espite some of the speculation, the president has not had any chest pain, nor was he evaluated or treated for any urgent or acute issues. Specifically, he did not undergo any specialized cardiac or neurologic evaluations."

Trump's health has largely been a black box. Earlier this month, Conley released a memo about a routine physical that provided little information beyond the president's height and weight -- 244 pounds and 6 feet 3 inches tall, putting him in the obese category with a BMI of 30.49 -- and blood pressure, along with a description of his use of hydroxychloroquine after potentially being exposed to staffers who tested positive for COVID-19.

It also indicated that Trump's cholesterol is now well controlled on a statin, falling to 167 from 196 last year.