How long does it actually take to form a New Habit(Backed by Science) Posted on 26 October 2015 at 20:31 Sometime in the recent past, our culture became obsessed with the idea that it takes 21 days (or 30 days or some other magical amount time) to build a new habit. This post not only explains how this happened, it also debunks the myth and shares the science behind how long it really takes to build a behavior that sticks...