This thread is insane, but your question is valid. I think I understand what you're asking, and you're wrong. Time slows down for the person in the space ship.
So suppose you get on a spaceship tomorrow that gets very close to the speed of light. You take a trip to, say, Alpha Centauri and back. Your best friend who you left on Earth, waits twenty-five years for you to come home and throws a party - but for you, it's only been about a year. So he's lost all his hair and you start dating his grandkid.
You, on the space ship, would eat and drink and age in a seemingly normal rate. It's only in comparison to the rest of the universe that you'd be slowed down. Does that make sense?
Yes and no.
We could live virtually forever, if not for thousands and thousands of years by traveling the speed of light, according to your premise.
The question I ask has more to do with human physiology than physics. Either you spend 4.36 years on a spaceship, or you don't. If you claim you actually do spend 4.36 years on a spaceship, then are you claming it has some physical effect on your body to keep it from aging? Can't be.
I don't understand your premise. If you are gone 25 years, your heart has to beat so many beats per second, per hour, per year. Are you claiming that traveling the speed of light somehow changes that principle? If time slows down, are you saying we would be in such a state of suspended animation that we would live 25 years would be the equivalent to 4 years in suspended animiation?
TO me it is not a coherent premise. But it is interesting.