We should probably just listen to his doctor, Dr. Ronny Jackson, who flooded the White House with all sorts of pills. He even had some nice dog whistles to eugenics to say about Trump.
"It's called genetics," Jackson said. "Some people just have great genes. I told the president if he had a healthier diet over the last 20 years he might live to be 200."
He also said Trump was 6' 3" and 239 lbs. except when they did his booking in NYC and Georgia it said something else. His NYC booking put his stats @ 6' 2" and 240 lbs., but then in Georgia a month later he was measured at 6' 3" and 215 lbs. meaning he gained an inch and lost 25 lbs.
And apparently some "expert" used a photo to determine Trump is really only 5' 11" when comparing him to his youngest son Barron who is 6' 7" tall.
But Trump very much believes in eugenics, so you have to read his report knowing that Trump was part of crafting every word of it. His German heritage, coupled with his fascination with Hitler, his father marching with the KKK, all make it hard to believe he isn't just telling you who he is.
Otherwise yes, some people hit the gene lotto and don't have risk factors to a lot of diseases. But that is not what Trump is talking about when he talks about genes, he thinks he is the "master race".
Edit - A piece on Trump's gene beliefs for context.