The 21 Day Habit Theory

I first know the "21 day habit theory" from the famous book "the 7 habits of highly effective people". I was wondering why its 21, not 10, nor 30 after that.

After some research, it seems that the 21 number comes from a doctor called Maxwell Maltz[1]:

“Dr. Maxwell Maltz, originally a plastic Surgeon, who also wrote the bestseller Psycho-Cybernetics, noticed that it took 21 days for amputees to cease feeling phantom sensations in the amputated limb. From further observations he found it took 21 days to create a new habit. Since then the '21 Day Habit Theory' has become an accepted part of self-help programs.”

The science behind this goes like this[1]:

“Brain circuits take engrams (memory traces), and produce neuroconnections and neuropathways only if they are bombarded for 21 days in a row. This means that our brain does not accept “new” data for a change of habit unless it is repeated each day for 21 days (without missing a day).” – Psycho-Cybernetics, A New Way to Get More Living Out of Life

"Without missing a day? Yes. Because your conscious mind creates the belief and the subconscious mind then executes the belief – it is important to keep on "fueling that fire" until it is self sustaining."[1]

But the number 21 doesn't change from habit to habit? It's our natural feeling that some habits are easier to form but others are much more hard.

There do be a formal research paper[3] on this problem in 2009. Their results show that the number 21 is not so accurate, it depends on what habit you are going to change and establish. The average days to form a habit in their research is 66, not 21. (see graph below)

habit forming days[2]

Anyway, the number is not so important, but the good news that habits CAN be changed and formed, if we put our efforts into it. But HOW?

Here are some good practices and tips on developing new habits:

1. Action Feeds Motivation: Motivation is not a 'feeling' that comes out of the blue. Action is the fuel that feeds motivation. You need to start doing something to get motivated.

2. Leverage Basic Instincts: "Human beings will do anything to avoid pain, and move towards pleasure." This basic instinct governs all your behavior. To change any habit, first figure out its base - does it give you any pleasure, or does it help you avoid some pain? Here, pain/pleasure means physical and/or emotional. Based on the basic instinct, decide how you can create 'pain' for the old habit you want to change so that you avoid it. Figure out how you can feel and enjoy pleasure whenever you indulge in the new habit.

"Celebrate each step, regardless how tiny it is." is another way to associate pleasure with habit change.

3. Make it Simple and Clear: Clarity and Simplicity make effectiveness. Write down your intentions, it's important to use positive affirmations to write these goals. What's more, instead of attempting a wholesale, huge life change, aim only for one behavior at a time. Break your goal down into smaller parts.

4. Ask Why: Persuade yourself before taking actions. The bigger your conviction, the easier it will be be for you to make the transition.

5. Stay Clear of Negative Triggers: There will be those who try to sabotage you. This doesn’t even have to be intentional. It could evolve from a negative statement aimed at you, or even a deep rooted belief you had since you can remember. Any trigger that could bring this out should be avoided.

Generally speaking, the first few days/weeks is the toughest. Once you cross the initial tough days, it only gets easier over time. Usually, the time can be divided into three phases:
1. 0-7 intentional, uncomfortable
2. 7-20 intentional, comfortable
3. 21-90 unintentional, comfortable, stabilizing phase

Form good habits and win in your life!

[Reference]

1. 21 Day Challenge – Develop New Habits
2. How Long to Form a Habit?
3. Paper: How are habits formed: Modelling habit formation in the real world

some Tips:
1. Changing Habits
2. 21 days to new habit
3. 一个月培养一个好习惯
4. 改变习惯只需21天