You can create a new habit in 66 days. But if you already enjoy something that's good for you, don't repeat it in a way that it becomes a habit. It loses the joy, says habits researcher Wendy Wood.
Wood, a professor of social psychology at the University of Southern California, has studied habits and their impact on thoughts, emotions and actions. She asserts that it's best to keep life's pleasures away from becoming habits:
With repetition, action tendencies become stronger. Feelings, however, become weaker with repetition. So, the more often you eat ice cream, the less pleasure you get from eating it. Philosophers refer to this as the difference between the "active" and "passive" components of habit. With repetition, our action tendencies get stronger but our feelings habituate and weaken.
The bottom line is that, if you really enjoy something, you don't want to repeat it in a routine way so that it becomes a habit. You lose the pleasure in the experience.
So what should you be looking to turn into habits? Wood advises focusing on the necessities, such as regular exercise, a healthy diet and saving money. She also says that it's best to link these with major events in your life. Her research shows it's easier to change habits when you are experiencing some change in how you live, such as moving houses, getting married or starting a new job with a new routine. You could also use other mind tricks to form new habits at the same time.
Habit Change is Easiest When People Move House or Undergo Some Life Transition [The Happiness Project]