There are countless diets that work on a 30-day or similar timeline. The inference is that after 30 days, the diet will be a habit. Why, then, do so many 30-day diets fail to become lifestyles?
Dr. Jan McBarron is an award-winning bariatric medicine physician, author and public speaker. Her goal is to promote healthy lifestyles which include eating well and regular exercise. As a physician, Dr. McBarron is all too familiar with the fad diets that come in 21-30-day programs, leaving her patients demotivated, frustrated, and blaming themselves. But, she says, the truth is that it takes much longer than 30 days to form a new habit.
The Truth About Developing Habits
The notion that it takes 30 days or less to form a reliable habit comes from the book Psycho-Cybernetics, published in 1960. In that book, plastic surgeon Dr. Maxwell Maltz writes that it takes a minimum of 21 days for patients to grow accustomed to changes in their body. For example, after 21 days, patients who had nose jobs begin to see their new nose as part of their self-image or patients who have lost a limb are slowly experiencing fewer phantom sensations. The book was a best-seller and soon the idea that 21 days was all it took for the brain to construct solid neuropathways was rampant.
Dr. McBarron cites a 2009 study from the European Journal of Social Psychology that asked 96 participants to form a single healthy habit. The study found that depending on the degree of change required to form that healthy habit (i.e. going from no regular exercise to exercising daily or drinking soda at dinner to drinking water instead), it took anywhere from 18 to an astounding 254 days to fully adopt the habit. Dr. McBarron recognizes going from a sedentary to an active lifestyle or changing that way you eat are huge adjustments and more likely to require more time.
Humans are indeed creatures of habit, says Dr. McBarron, and therefore breaking habits takes time and persistence. Because we are likely to repeat our habits daily, the neuropathways in our brains that control those habits are solid. Developing new habits requires not only building new neuropathways, but also replacing old ones. The human brain will always choose the path of least resistance and changing habits requires dedication and commitment.
Instead of focusing on a specific timeline, Dr. McBarron recommends focusing on the times you succeed. Often, change is not a linear path. There will be days when you have a cheat meal or miss the gym. The important thing is that you consistently make the effort to develop your new habits through repetition, repetition, repetition. Whether it takes 18 or 254 days to build your new habits, the important thing is persistence. Eventually, says Dr. McBarron, you will succeed.