This Is How Long It Really Takes To Form A Habit (Hint: It’s Not 21 Days)

Photographed by Anna Jay
A few years ago, I set out on a very specific quest. I wanted to start making my bed every single day. It did not come naturally. It was against my “chaotic good” principles, really, but I’d heard on good authority (from people I believed to be more organised than I) that the habit could change my life.  They said that with the commanding sweep of a comforter every morning, I could potentially bring order to my cluttered social calendar and messy desk. It would trickle over into every aspect of my life, they promised.
I remembered that in high school, one of my coaches told me it takes 21 days to form a habit. So, I figured I’d begrudgingly arrange my throw pillows for 21 days straight, and eventually it would come to me automatically. Maybe it would even become fun. But after 21 rough days of forcing myself to untangle my sheets at 7 a.m., even on days I was running late, I found that I hated this task more than ever. By day 22, I still despised making the crisp folds, so I quit. I would always just be a little bit worse at life than bed-makers, I figured. Whatever. 
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But as it turns out, I was approaching it all wrong. The 21-day rule is a myth. Or more accurately, it's a misinterpretation of something plastic surgeon Maxwell Maltz wrote in his popular book about behaviour, Psycho-Cybernetics.
When Maltz did an operation on a patient — whether it was a nose job or a leg amputation — he noticed it would take them 21 days to adjust to the change in their body. Based on that, he wrote in his book that “it requires a minimum of about 21 days for an old mental image to dissolve.” And, as this idea spread, people started dropping the “minimum of” part, writes James Clear, author of Atomic Habits: An Easy & Proven Way To Build Good Habits and Break Bad Ones.
But those two words are kind of important. Without them, the idea that it takes exactly 21 days to form a habit became a widely reported, widely repeated fact — when in reality, the whole idea is based on the opinion of one plastic surgeon.
Research summarily discredits the “21-day rule.” Phillippa Lally, PhD, a senior researcher at University College London, published a study that found it actually takes an average of 66 days — more than two months – to form a habit. Lally also reported that the amount of time before a new behaviour feels automatic can range between 18 and 254 days.
“We don't really know what predicts the variation in times,” Lally says. But she does have a hunch: “It’s likely easier to consider that [a habit] feels automatic when it's a simpler behavior," Lally says. Drinking a glass of water in the morning requires less work than starting to exercise regularly, for example; so you may feel as though you're able to incorporate the former into your routine more quickly than the latter.
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I had mixed feelings about this news. There was something about the 21-day rule that seemed comforting and manageable to me. I could do almost anything for less than a month.
But the fact that it’s been debunked is also empowering. It means that rote repetition for three weeks straight isn't the only way to form a new routine. No more feeling guilty if you miss a day, like I did when I was trying to train myself to make my bed. (In addition to disproving the 21 number, Lally's study also found that missing a day when you're on a streak doesn't hinder the habit-forming process.)
I can also quit feeling like a failure for eventually quitting entirely. “There’s no reason to get down on yourself if you try something for a few weeks and it doesn't become a habit,” Clear writes on his website. “It's supposed to take longer than that!” 
But if the 21-day rule is bogus, how do you really break or make a habit? Lally says there are research-backed methods that really work.
One way to make success more likely is to only form habits you genuinely want to incorporate into your life, Lally says. Then, set up cues that will prompt you to complete them. For example, you probably already brush your teeth every day, so use it as a prompt for flossing — put your spool right next to your toothpaste, so you'll never forget. The idea is to concentrate on (1) remembering to do the habit and (2) staying motivated. Most likely, it will get easier to repeat the habit over time; you won't struggle every day right up until day 66, then suddenly have the routine "click."
Maybe I’ll try making my bed all over again and see what happens on day 255. Or maybe I'll take Lally's advice and focus my energy on picking up a habit that doesn't feel like torture (like writing in my gratitude journal every morning) and leave that Made-Bed Energy to the morning people.

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