Perhaps you’ve heard it said that if you want to form a new habit—say, flossing your teeth or exercising regularly—all you have to do is perform that act for 21 days in a row, and presto! The desired behavior becomes automatic.
That, my friend, is a steaming pile of horse and dog shit, all mashed together and stirred to a pungent paste. This “21 days” notion is a distorted version of something that a plastic surgeon named Maxwell Maltz once wrote. In his 1960 book Psycho-Cybernetics, Maltz observed that it took roughly 21 days for his patients to start adjusting to their new appearances. He then proposed that this also applied in certain other situations, such as getting used to living in a new home.
With the aid of various authors, motivational speakers and self-help gurus, Maltz’ statement—which, by the way, was about habituation, not habit formation—took on some serious nips and tucks as it traveled from mind to mind. In the public imagination, 21 became the magic number for habit-building of all types. Countless 21-day habit challenges were soon spawned, not to mention books with titles like 21 Days Building Healthy Habits for Your Family and The 21 Day Miracle: How to Change Anything in 3 Short Weeks.
There are plenty of variations on this fundamentally flawed idea. You’ll hear some sources say it takes 14 days to form a new habit, and others 28. One of the most recent, and presumably most accurate, figures comes from a study published in 2009, which found that it can take anywhere from 18 to 254 days to adopt a new habit, with 66 days as the average. (66 happens to be the number of days MUD\WTR uses for its employee habit challenges.)
With all the misconceptions and conflicting information around this subject, Trends w/ Benefits reached out to a couple of experts for their takes on the million-dollar question:
How Long Does It Really Take to Form a New Habit?
We’re not going to bury the lede here—the short answer is, “It’s complicated.” At least that’s how Dr. Benjamin Gardner of England’s University of Surrey sees it. As an expert on the psychology of habitual behavior, Gardner has been exploring the mechanics of habit and behavior change for more than 15 years.
“It's not the case that we have a habit or we don't have a habit,” he tells us. “It's better to think of habit as happening like a kind of continuum of strength, so things get more habitual over time, or if we haven't done them for some time, or if we try to override them, they become less habitual. It's not that there's a kind of magic point beyond which suddenly we go from ‘I had no habit before this,’ to ‘I now have a habit.’ I think that's why there's such variation.”
We got a similar “It’s complicated”-style answer from behavioral scientist Katy Milkman, Ph.D. Along with being a professor at the University of Pennsylvania’s Wharton School, Milkman is the co-founder and co-director of the Behavior Change for Good Initiative and the author of the national bestseller How to Change. She was involved in a study of habit formation at the California Institute of Technology. The data from that study allowed researchers to compare the amount of time it took to form a habit of going to the gym against the amount of time it took hospital caregivers to form a habit around hand sanitizing. As Milkman notes, the results varied broadly.
“The average across this very wide distribution of both samples is hugely different, so gym attendees’ habits take way longer to form than habits around sanitizing your hands,” she says. “Maybe that's because you don't go to the gym as frequently, so high-frequency repetition forms habits better, or maybe it's because one [activity involves] very fine motor activity, and the other is much more complex. So what that suggests is that it's probably going to be very domain-specific, and it's personal. That doesn't mean you can't estimate how long it takes to form habits, but there's no magic number.”
But We Like Magic Numbers!
The results of the Caltech research illustrate some of the factors that make it tricky to pin down just how long habit formation takes. For example, the study underscores the principle that habits form through repetition. “If it's easier to repeat [the action] at a higher frequency, it makes sense that it will become habitual faster,” Milkman notes.
As shown in the study, as well as in the aforementioned research by Phillipa Lally and her peers, there’s also a tendency for simpler behaviors, such as drinking a glass of water, to become habitual more quickly than complex behaviors, such as doing 50 sit-ups.
Milkman compares the process of habit formation to that of learning. “If you think about making coffee with a fancy new coffeemaker, how long before you can do all the steps without thinking depends on how complex your coffeemaker is,” she offers.
Adding to the list of variables is the fact that some habits pack a higher reward value than others, thus inviting a higher level of motivation.
And then, of course, some people are simply better suited to forming habits than others. For instance, high levels of conscientiousness in individuals have been linked to habit formation. Or, as Gardner notes, “People who have the need for routine and who need things to be structured and ordered in their lives are more likely to go on and form habits.”
Stop Counting the Days
“[My research partners and I] have spoken to people who are trying to do something once a day every day,” Gardner says. “They report back that it tends to take them within one to two weeks for it to start feeling like it's becoming part of their routine, start feeling like it's becoming second-nature or just something that's them, and it's what they do. So, I'd probably say it's about two weeks to start to feel like you're on the right track for forming a habit.”
The bad news: If accuracy is important to you, that’s probably the closest thing to a concrete statement on this subject that you’re going to get. With all the variables at play, there’s just no definitive amount of time that it takes new habits to stabilize.
That also happens to be the good news, because it means that if you haven’t been able to hit your target in 21 days, 28 days or even 66 days, you haven’t necessarily failed. Just stay the course, set realistic goals, remove as many obstacles to those goals as possible and do what you can to make the desired behavior fun. For example, Milkman suggests only allowing yourself to binge-watch your favorite TV shows while you’re exercising at the gym.
“You want to align what's enjoyable with what's good for you in the long run,” she says. “That's where you get habits.”
Damon Orion is a writer, musician, artist, and teacher based in Santa Cruz, Calif. He has written for Revolver, Guitar World, Spirituality & Health, Classic Rock, High Times and other publications. Read more of his work at damonorion.com.