#EvidenceBasedPractice

New research debunks the popular belief that new habits form in 21 days. In reality, a behavior often becomes automatic after about two months, with some habits taking nearly a year. This matters for Thais aiming to eat healthier, exercise regularly, learn a language, or practice daily routines.

The idea of 21 days comes from a 1960 book by a plastic surgeon observing his patients. Over time, that anecdote was misread as science. Since then, multiple studies have clarified the timeline. A landmark study from University College London tracked 96 people over 12 weeks and found habit formation varied from 18 to 254 days, with an average around 66 days. Complexity and consistency mattered most to the outcome.

Emerging scientific research has shattered the widely-believed myth that forming a new habit takes just 21 days, revealing instead that it can require anywhere from two months to nearly a year for a behavior to become truly automatic. For Thais striving for change—whether adopting healthier lifestyles, cultivating language learning routines, or building positive daily practices—these findings offer both a reality check and a roadmap for lasting personal improvement.

The idea that new habits can be formed in just three weeks traces its roots to a 1960 book, “Psycho-Cybernetics,” written by plastic surgeon Maxwell Maltz. Maltz observed his patients adjusting to physical changes in about 21 days, but his anecdotal reflections were gradually misinterpreted over decades as scientific fact, mutating into an inspirational but flawed self-help mantra (James Clear; Scientific American). This “21-day” concept took off because it felt both achievable and motivating—even if it lacked solid scientific footing.

A new randomized controlled trial suggests that self-paced, low-to-moderate aquatic exercise can meaningfully improve physical function and mental well-being for people with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). The six-month study, led by a senior researcher from a regional university in Australia, enrolled 32 adults around age 55 and compared a water-based program to usual activities. The findings offer a cautious path forward for exercise recommendations in ME/CFS, a condition long approached with rest due to concerns about post-exertional malaise (PEM).

A recent breakthrough study suggests that low- to moderate-intensity aquatic exercise can significantly improve both physical and psychosocial well-being in people living with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), bringing new hope for a condition often marked by persistent fatigue and limited treatment options. Published on April 17, 2025, and led by Dr. Suzanne Broadbent, Associate Professor of Clinical Exercise Physiology at the University of the Sunshine Coast, this randomized controlled trial (RCT) challenges the longstanding caution against physical activity for ME/CFS patients—a group that also includes a high proportion of those battling fibromyalgia symptoms.