Changing habits—whether it’s eating healthier, exercising more, or going to bed earlier—can feel like an uphill battle.
A major new study has analyzed how long it actually takes for a new behavior to become second nature, and the results might surprise you.
There’s No Magic Number
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Forget the popular belief that it takes 21 days to form a habit. That number comes from a 1960s book by a plastic surgeon, not scientific research.
The truth is that habit formation varies widely from person to person.
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Science Says About Two Months—But It Depends
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A large-scale analysis of 20 studies found that, on average, new habits start to stick after about two months.
However, some people form habits in just a few days, while others take a year or more.
Daily Repetition Speeds Things Up
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The more often you repeat a behavior, the faster it becomes automatic. If it’s something you do multiple times a day—like drinking water—you’ll form the habit quicker than something you only do once a week.
Mornings Are the Best Time for New Habits
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Research suggests that morning routines provide the best chance of success.
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When you attach a new habit to an existing morning ritual—like stretching after brushing your teeth—it becomes easier to maintain.
Planning Increases Your Odds of Success
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Setting yourself up for success matters. If you prepare your gym clothes the night before or pre-cut vegetables for healthy snacks, you’re more likely to stick to your new habit.
Enjoyment Makes a Huge Difference
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You’re far more likely to form a habit if you actually enjoy it. If you hate running, you might struggle to make it a daily routine.
But if you love dancing or cycling, those activities will naturally become part of your life.
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Habits Stick Faster When Tied to a Reward
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Positive reinforcement strengthens habits. If you associate a behavior with a reward—like treating yourself to a smoothie after a workout—it’s more likely to become part of your routine.
External Pressure Can Help—Or Hurt
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Some habits form quickly when there’s an urgent reason behind them. During the COVID-19 pandemic, mask-wearing became an instant habit for many due to the perceived risk.
On the flip side, forced habits without personal motivation often fade fast.
Breaking Bad Habits Is Harder Than Making New Ones
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Unlearning an old habit is usually tougher than forming a new one.
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If a behavior is tied to addiction—like smoking or excessive screen time—it requires conscious effort and often multiple attempts to change.
There’s No One-Size-Fits-All Timeline
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Ultimately, how long it takes to form a habit depends on the individual, the behavior, and the context.
What works for one person might not work for another, so patience and persistence are key.
Article based on information from Videnskab.dk
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