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Stop Expecting to Change Your Habit in 21 Days

How long does it really take to change a habit?

In my research on happiness, I keep running into the assertion that it takes 21 days to develop a new habit—but I’ve always had my doubts about the validity of that number.

First, when it comes to developing a bad habit, two repetitions is probably enough. Order a doughnut with your coffee on Monday morning and Tuesday morning, and you’ll probably find it very hard to resist ordering a doughnut on Wednesday.

Second, at least for me, 21 days isn't nearly long enough to form a good habit. For my happiness project, I tried for many weeks to get in the habit of keeping a food journal, and I failed and gave up, and then tried again, and I never could get in the habit. Flossing is a challenge—though all the suggestions from these commenters have improved my flossing rate, I must say. Even writing in my one-sentence journal, which I enjoy doing, isn't really quite habitual yet.

Because I’ve always questioned that often-repeated statistic, I was very interested to read Oliver Burkeman’s article, "How long does it really take to change a habit?"

According to a recent study, a daily action like eating fruit at lunch or running for 15 minutes took an average of 66 days to become as much of a habit as it would ever become.

However, there was a lot of variation, both among people and among habits—some people are more habit-resistant than others, and some habits are harder to pick up than others.

I found this study reassuring. My difficulty in picking up certain habits wasn't unusual. Fact is, habits are hard to alter, and that’s why developing a good habit is really worth the struggle; once you’re used to making your bed each morning, or going for an evening walk, or flossing, you don’t have to exert much self-control to keep it up.

The study also showed that if you miss a day here or there when you’re trying to develop a habit, it doesn’t derail the process, so don’t get discouraged if you can’t keep a perfect track record. But the first days seem to make the biggest difference, so it’s worth trying to be particularly diligent at the beginning of the attempted-habit-acquisition process.

What do you think? What has been your experience in developing habits? How long has it taken, and what tricks have you found to help yourself acquire—or kick—a habit?

*Interested in starting your own happiness project? If you’d like to take a look at my personal Resolutions Chart, for inspiration, just email me at grubin, then the “at” sign, then gretchenrubin dot com. (Sorry about writing it in that roundabout way; I’m trying to thwart spammers.) Just write “Resolutions Chart” in the subject line.

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