I'm not saying this isn't possible, as some simple lifeforms seem to be basically immortal but our systems are much more complex and consist of many more moving parts and we are just meat machines. Machines wear out and you have to replace the parts. We're no where near being able to replace all of our parts. So there is a pretty good reason why at least the people currently alive aren't going to see what you're saying come to fruition. Entropy is a bitch.