I see a Vance in under two years.
https://obesityreporter.com/life-expectancy-morbidly-obese/
some one as fat as trump on average dies six years sooner.
so 8.95-6= 2.95 years or less on average.
That takes things a bit in isolation though. Also consider that he's apparently in decent health (if you don't watch MSNBC), active, doesn't drink, doesn't smoke, will have the best doctors in the world available to him and is wealthy (though that is likely a redundancy up against being president) and you might want to account things a little differently.
Then again, anyone can keel over at any time so there are no guarantees.
Edit: Oh, and apparently he isn't morbidly obese in any case (even with worst estimates): https://www.statesman.com/story/news/politics/elections/2020/05/20/fact-check-is-donald-trump-morbidly-obese/984117007/ I wouldn't trust a word out of Pelosi's lips (other than when she's describing how they do the wrap-up smear).
Pelosi called Trump "morbidly obese."
Based off of his declared height and weight, Trump has a body mass index of 30.1. This places him into the lowest of three levels under the CDC’s definition of obesity. Even if the public numbers are a bit shy of reality, Trump would have to be substantially heavier to meet a level of severe, or morbid, obesity.
We rate Pelosi’s claim False.
Biden was also showing signs while running in 2019 for anyone who wasn't refusing to see them. I was actually surprised they managed to keep him propped up as long as they did. He also had a history of medical issues, some brain related.