The New Science on Making Healthy Habits Stick

How long does it take to build better diet and exercise routines? Here are science-backed strategies

By: Alex Janin 
September 27, 2023 

PHOTO ILLUSTRATION BY ELENA SCOTTI/THE WALL STREET JOURNAL, ISTOCK (2)
 

Any healthy choice seems doable for a day. Building consistent good habits around exercise, sleep and nutrition in the long term is harder. 

Recent research is uncovering how long it takes to cement different kinds of habits—and gives fresh insight into how to make them stick. Simple health habits like handwashing, for instance, take a couple of weeks to develop, while more complicated ones like going to the gym take four to seven months, according to a recent study. 

“You can’t mindlessly go to the gym the way you mindlessly shampoo your hair,” says Katy Milkman, a professor at the University of Pennsylvania’s Wharton School and co-author of the study, which was published in Proceedings of the National Academy of Sciences.

One big lesson if you’re trying to establish a new healthy habit: You will have better luck if you can simplify the process and repeat it often. Finding ways to make it fun and setting realistic expectations about how long it will take to establish the habit will help too, other research has found. 

Cheryl A. Johnson struggled over decades to keep a consistent exercise routine before she moved to her current home in Greenville, N.C., and invested in a swimming pool. She estimates it took more than a year to adopt a regular swimming routine after the pool was installed, working on breathing techniques and getting over the fear of putting her face in the water. Now, she has been swimming consistently for seven years.

“I learned that if you don’t give yourself grace, you feel like you’re failing every day,” says Johnson, 63. 

Here are some of the best science-backed strategies that can help you build healthy habits more efficiently.
 

Simplify and repeat

A landmark 2009 study by researchers in the U.K. found that simple health habits, such as eating a piece of fruit with lunch or running for 15 minutes before dinner, took an average of 66 days to form. Two to three months is a safe bet on average, behavioral researchers say, but the more complex the behavior, the more difficult it is going to be to put on autopilot.

Habits likely develop more quickly the more often they are repeated, says Milkman, and lessening your decision-making helps too. 

If you are trying to go to the gym regularly, reduce the amount of time and effort required by incorporating it into your work commute. That could mean choosing a gym between your home and workplace and keeping a bag with clean workout clothes in the back of your car, says Wendy Wood, a professor of psychology and business at the University of Southern California, whose research focuses on habit formation. 

Eliminating the chances of making decisions that could tempt you from your desired path can be helpful. If you want to cook healthier meals, fill your fridge with fresh produce. If you want to stop doomscrolling at night, ditch the charging cable next to your bed and replace it with a good book. 

For those hoping to use social media less, keeping Facebook and Instagram apps on their phone’s home screen is akin to “having an open bag of Skittles in your pocket at any given time,” says Brad Stulberg, adjunct professor at the University of Michigan’s School of Public Health and an executive coach. 
 

Plan, but be flexible

Repetition and planning are essential tools in developing habits efficiently, behavioral researchers say. But rigidity can make follow-through harder in the long run. 

When a team of researchers conducted a study of gymgoers who were paid to work out on a consistent schedule versus a variable schedule, they were surprised to find that those with more variable schedules went to the gym more overall once the payments stopped, says Milkman, who co-wrote the study. 

Those participants had backup plans, such as going to the gym in the evening if they missed the morning slot. The lesson, she says, is to avoid a rigid, “7 a.m. or bust” schedule that doesn’t allow for different ways to achieve your habit if your original plan falls through.
 

Expect to feel worse at first

We expect healthy habits to make us feel better—more energetic, sated, stronger or calmer—but those feelings don’t often come right away.

Starting a new behavior, such as cutting out screen time before bed, cooking more or exercising before work, prompts the body and brain to cycle through a state of order, disorder and reorder, also known as allostasis, says the University of Michigan’s Stulberg.

This is what leads us to feel worse before we feel better, he says. Starting a new gym habit, for example, might lead to muscle soreness, hunger and fatigue before we start to feel the benefits and adapt to the new routine. 

“If you don’t expect it to be hard, then when it is hard you freak out and you quit,” says Stulberg. 

Make it fun

If the habit itself isn’t enjoyable, finding other ways to make it fun can help make the habit stick, researchers suggest.

Wood, the USC professor, enjoys trashy novels but only allows herself to read them when she is working out on her elliptical machine. Milkman calls this strategy “temptation bundling,” or encouraging an action by letting yourself enjoy something only while doing it. Thinking about the long-term value of a habit often does little to motivate us at present, she says. 

“We should spend more time focusing on the instant gratification we get from the activities we want to put on autopilot,” she says. “It needs to be rewarding in the moment.”