>>2035Multicellular organisms are all a ship of theseus. It's true, a majority of your cells last several years at most, but that's not particularly relevant. You shouldn't think of cells as indepedent, when they mostly can't survive if they're separated from the whole. The being remains itself through the continuity of the system, not of its parts.
If you want to get technical, everything that undergoes any form of change is different from what it was seconds ago, even a rock whose particles gradually shift into a different composition and ultimately end up as something else entirely. But it doesn't really matter, the question of an essential you is founded on the prior assumption of the existence of a static and unchanging soul. If you believe in a transcendental essence then you've always been you and will always be, if you don't believe in it then there's simply no essence to begin with.