Healthy Habits Take Time: Systematic Review Debunks 21-Day Habit Myth - Video

In a new systematic review, UniSA researchers found that new habits can begin forming within about two months (median of 59-66 days) but can take up to 335 days to establish. The findings are published in journal Healthcare. It’s an important finding that could inform health interventions to promote healthy behaviours and prevent chronic disease.

The study of more than 2600 participants also found that certain factors can influence successful habit formation.

“Adopting healthy habits is essential for long-term well-being but forming these habits – and breaking unhealthy ones – can be challenging,” University of South Australia researcher, Dr Ben Singh, says

“At the beginning of the year, many of us are setting goals and making plans for the months ahead –things like being more active, cutting back on sugar, or making healthier food choices – but while common wisdom suggests that it takes just 21 days to form such habits, these claims are not evidence-based.

“In our research, we’ve found that habit formation starts within around two months, but there is significant variability, with formation times ranging from four days to nearly a year.

“So, it’s important for people who are hoping to make healthier habits not to give up at that mythical three-week mark.”

Reference: Singh, B., Murphy, A., Maher, C., & Smith, A. E. (2024). Time to Form a Habit: A Systematic Review and Meta-Analysis of Health Behaviour Habit Formation and Its Determinants. Healthcare, 12(23), 2488. https://doi.org/10.3390/healthcare12232488