It's hard to break a bad habit

If you know something's bad for you, why can't you just stop?

About 70 percent of smokers say they would like to quit. Drug and alcohol abusers struggle to give up addictions that hurt their bodies and tear apart families and friendships. And many of us have unhealthy excess weight that we could lose if only we would eat right and exercise more. So why don't we do it?

National Institutes of Health scientists have been studying what happens in our brains as habits form. They've found clues to why bad habits, once established, are so difficult to kick. And they're developing strategies to help us make the changes we'd like to make.

Habits can arise through repetition. They are a normal part of life and are often helpful.

"We wake up every morning, shower, comb our hair or brush our teeth without being aware of it," Dr. Nora Volkow says. "When behaviors become automatic, it gives us an advantage, because the brain does not have to use conscious thought to perform the activity."

This frees up our brains to focus on different things.

Habits can also develop when good or enjoyable events trigger the brain's "reward" centers. This can set up potentially harmful routines such as over-eating, smoking, drug or alcohol abuse, gambling and even compulsive use of computers and social media.

"The general machinery by which we build both kinds of habits are the same, whether it's a habit for over-eating or a habit for getting to work without really thinking about the details," says Dr. Russell Poldrack, a neurobiologist at the University of Texas at Austin. Both types of habits are based on the same types of brain mechanisms.

But, the pleasure-based habits are harder to break. Enjoyable behaviors prompt the brain to release a chemical called dopamine that strengthens the habit even more.

Volkow notes that there's no single effective way to break bad habits.

One approach is to focus on becoming more aware of your unhealthy habits. Then develop strategies to counteract them. For example, habits can be linked in our minds to certain places and activities. You could develop a plan, say, to avoid walking down the hall where there's a candy machine. Resolve to avoid going places where you've usually smoked. Stay away from friends and situations linked to problem drinking or drug use. If you always stop for a doughnut on your way to work, try a different route. Keep fatty foods, cigarettes, alcohol and other tempting items out of your home.

Another helpful technique is to visualize yourself in a tempting situation. If you can't avoid the situation, think about how you want to handle it. Mentally practice the good behavior over the bad. If you'll be at a party and want to eat vegetables instead of fattening foods, then mentally visualize yourself doing that. It's not guaranteed to work, but it certainly can help.

One way to kick bad habits is to actively replace unhealthy routines with new, healthy ones. Some people find they can replace a bad habit, even drug addiction, with another behavior, like exercising.

Certain groups of patients who have a history of serious addictions can engage in certain behaviors that are ritualistic and in a way compulsive -- such as marathon running -- and it helps them stay away from drugs. These alternative behaviors can counteract the urges to repeat a behavior to take a drug.

Enlist support. Ask friends, family and co-workers to support your efforts to change. Reward yourself for small steps. Give yourself a healthy treat when you've achieved a small goal or milestone.

Information for this article came from News in Health, a monthly newsletter from the National Institutes of Health, part of the U.S. Department of Health and Human Services.