We've Been Lied To! It Takes More Than 21 Days To Build A Habit, Study Reveals Real Timeline

The concept that any behavior can only take 21 days to cement has been quite the popular idea around habit formation for decades now. Self-help books, motivational speakers and productivity gurus have been assuring millions in recent years that a mere three weeks of commitment would be more than enough for turning a behavioral routine into some lifelong habit. But new evidence from the University of South Australia shatters just that long-standing myth, challenging how we perceived the process for developing habits long after.

New habits usually become automatic after around two months; however, the time varies among individuals, while some may even take nearly one year. Researchers from UniSA conducted a meta-analysis of studies published in the journal Healthcare on 20 researches that included over 2,600 participants between 2008 and 2023, which monitored habits such as working out regularly, drinking more water, taking vitamins, and flossing each day.

A large variety was observed with regards to the duration of habit formation, ranging between 59 to 66 days in the center. It further goes down as some reported getting habits as quickly as within four days and went up as long as 335 days in one case. There seems to be a high need for determining some underlying variable associated with the time required by such behavior for a habitual practice in this comparison of findings.

This myth that habits take 21 days to form originated in Maxwell Maltz's book, Psycho-Cybernetics, written in 1960. Maltz, a plastic surgeon, found that it took his patients an average of 21 days to get used to their new looks following surgery. In the years that followed, Maltz's anecdotal evidence transformed into a universal mantra of self-improvement without scientific support. This new UniSA study explodes this myth by providing a better evidence-based view of how habits really work.

Why Do Some Habits Take Longer to Stick?

Several factors determine how long it takes to form a habit. The frequency of repetition plays a significant role—daily habits like drinking water or flossing tend to solidify faster than sporadic ones, such as going to the gym three times a week. Enjoyment and motivation are crucial; people are more likely to stick with habits they find pleasurable. For example, incorporating music into a workout routine can make exercise more appealing and sustainable.

Timing and routine also impact habit formation. Integrating a new behavior into an existing routine—such as flossing right after brushing your teeth—can help reinforce consistency. Environmental triggers are another key factor; placing a water bottle on your desk serves as a visual cue to stay hydrated, while removing barriers to a habit’s success makes it easier to maintain.

Finally, resilience and consistency determine long-term success. It is normal to make occasional slip-ups, but the ability to recover quickly matters more than avoiding mistakes entirely. Missing a day or two won't derail habit formation, but prolonged inconsistency can make it harder to sustain.

Also Read: How Can You Use Habit Stacking For Self Improvement

According to bestselling author James Clear, who wrote Atomic Habits, forming new habits requires strategic implementation. Here are some research-backed strategies:

1. Start Small

Begin with an easy, manageable version of your desired habit. Instead of committing to 50 pushups a day, start with five.

2. Increase Gradually

Progress should be incremental. Small, consistent improvements compound over time and lead to sustainable change.

3. Break It Down

Rather than aiming for one massive goal, break the habit into smaller, digestible chunks to maintain momentum.

4. Bounce Back Quickly

Mistakes happen, but getting back on track immediately helps reinforce consistency and prevents discouragement.

5. Be Patient

Patience is key—habits take time. Instead of rushing, focus on creating a pace that is sustainable in the long run.

10 New and Healthy Practices You Can Start Today

If you're looking to develop new healthy habits, consider starting with one of these:

1. Ditch smoking for better lung health.

2. Prioritize quality sleep.

3. Find joy in exercises that you would really like.

4. Provide love and compassion daily.

5. Eat wisely. Pay attention to your hunger levels.

6. Limit or remove processed food consumption.

7. Reduce consumption of added sugars

8. Do gratitude journals

9. Separate work from other aspects of your life

10. Checkup on your mental health.

This research now contests the old rule about habit formation needing to be within 21 days and other theories that throw light upon habit variability. The same behavior may exert its influence within weeks in some individuals, but in others, it may take months or nearly an entire year to sink in. Knowing this helps keep one patient, persistent, and realistic when trying to form lasting habits.

A Systematic Review and Meta-Analysis of Health Behaviour Habit Formation and Its Determinants.Healthcare 2024

Making health habitual: the psychology of 'habit-formation' and general practice. Br J Gen Pract. 2012