Debunking the 21-Day Habit Myth: How Long Does It Really Take to Form Healthy Habits?

We've all heard the age-old advice that it takes just 21 days to form a new habit. But have you ever wondered where this idea originated and whether it's actually true? As it turns out, this popular notion can be traced back to plastic surgeon Maxwell Maltz and his observations in the 1960s. However, it's important to recognise that adjusting to a new self-image after surgery isn't quite the same as adopting and maintaining healthy lifestyle habits. In this article, we'll dive into recent research conducted by behaviour change scientist Katy Milkman to uncover the truth about habit formation.

The Study's Approach:

To unravel the mysteries of habit formation, Katy Milkman and her team embarked on a comprehensive study. They investigated two very different habits: going to the gym and hand-washing by hospital workers. The former is a health-conscious choice, while the latter is a mandatory practice governed by health and safety regulations.

For gym habits, the researchers collaborated with a major gym chain, tracking 30,000 members' gym check-ins over four years. Each swipe of a membership card was meticulously recorded. Simultaneously, around 3,000 healthcare workers were monitored over 100 shifts, using special badges to record their hand-washing behaviours. This massive dataset formed the basis for their analysis.

The Power of Machine Learning:

Rather than manually scrutinising the data, the researchers employed machine learning techniques to uncover patterns and trends. This approach allowed them to explore variables that might have otherwise been overlooked. By letting computers identify which factors most influenced individual behaviours, they minimised the potential for confirmation bias.