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The 21-40-90 Rule - How New Habits are Formed

Everyone has heard the expression "Habit is formed in 21 days." So most think that if you do the same thing for 21 days, you will get used to it and voila! Through personal experience I can tell you that this is not the case. Not even close. But the first 21 days are crucial in creating and forming new habits.

Let me explain a little further: to make a habit become second nature, you need exactly 90 days. After 21 days, the habit is only being formed, but the old habits continues to circulate. After 40 days, the old habit begins to take a second place, but it is still “visible”, although not as clearly. And only on the 90th day the new habits take its most flourished form.

The essence of a habit is memory. And memory is a chemical rather than a psychological process, and it works something like this: we receive information through analyzers, they excite a certain portion of the cerebral cortex, for some time this excitement circulates through the neural circuit, dying out and being lost in the depths of other excitations. To maintain circulation, you need to regularly repeat what you want to get used to. If the circulation of a new stimulus occurs on an ongoing basis - the short-term memory becomes long-term. And then, pure chemistry: changing the protein composition of the cell. A memory appears that reinforces the change in the speed of a nerve impulse. As a result, the memory is fixed and activated upon the next receipt of the impulse.

If you are asking yourself: “what did I just read?” Let me simplify: The brain frantically forms a connection between an object of affection (a banana instead of candy) and the excitement of a certain proportion of the cerebral cortex (delicious!). Every time we are creating a new habit, this excitement for a while wanders through the neural circuit (banana, banana, banana), or fades away (candy, candy, candy) if we do not repeat the action. So, it depends on the number of repetitions, whether this habit remains in short-term memory or in long-term one (whichever one is used more, wins).

21 day - forming a new habit

21 days - the first milestone on a new path. To adopt a new habit, you need about the same amount of time to weaken the bonds that is no longer used. This happens in 40 days. So, after 21 days we choose to either go back to the old, usual path that is still visible or continue on the newly laid out one that is a lot more beneficial for us.

40 days - still requires effort During the 40 days, the old habits begin to phase out, and become less visible because the new habits are right upfront and being repeated over and over again. However, during this time, the new habits are still not automatic - it takes some effort to follow through. This is the period of consolidation of the habit.

90 days - out of the woods

If you have reached the 90 day mark, the new habits have steadily entered your life. You will no longer need to strain or put much effort into following the new habits. The action becomes automatic.

To sum it up: In general, it takes about 90 days for your intention to become a single neural connection, where your hand automatically reaches for a banana, and not for candy. But 21 days is where it all begins, can't get to 40 or 90 without 21. So it’s a start, an important one where you begin to move from old to new.

For those of you who are doing the 21 Day Program with me starting December 3rd, it’s just the beginning and I am so happy you committed, and it's ALL WORTH IT because YOU ARE WORTH IT!!

Yours truly,


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