Charles Duhigg, author of The Power of Habit: Why We Do What We Do In Life and Business, defines a keystone habit as “changes or habits that people introduce into their routines that unintentionally carry over into other aspects of their lives.” Think of a keystone habit as a pebble thrown into a pond that creates multiple ripples or additional benefits in your life. For my clients, getting their food in order is a keystone habit that automatically carries over to other areas of their lives.