You activate telomerase, you repair those telomeres and extend them on all of your healthy cells, you could live forever. That's how cancer is able to replicate foreverāit extends the telomeres. But it's better observed in planarians, where it naturally occurs with correct cell cycle checks. A planarian does grow old as it lives, but as soon as you cut them in half, their stem cells work to create the new half of them and they're basically reset to a new planarian. They are revitalized. They are young again. Even their old cells reset to young. You can grow a whole new worm from a
SINGLE CELL! WOW!