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Changing One Bad Habit has Domino Effect

A new Northwestern Medicine® study reports that simply changing one bad habit has a domino effect on others. Two key behavior changes are most effective:  cutting time spent in front of a TV or computer screen and eating more fruits and vegetables.

“Americans have all these unhealthy behaviors that put them at high risk for heart disease and cancer, but it is hard for them and their doctors to know where to begin to change,” said Bonnie Spring, PhD, a professor of preventive medicine at Northwestern University Feinberg School of Medicine, and lead author of the study published in Archives of Internal Medicine. “This approach simplifies it.”

Spring wanted to figure out the most effective way to spur people to change common bad health habits. She and colleagues randomly assigned 204 adult patients, ages 21 to 60 years old, with unhealthy habits into one of four treatments: increase fruit/vegetable intake and physical activity, decrease fat and sedentary leisure, decrease fat and increase physical activity, and increase fruit/vegetable intake and decrease sedentary leisure.

During the three weeks of treatment, patients entered their daily data into a personal digital assistant, earning $175. But when that phase was completed, patients no longer had to maintain the lifestyle changes to be paid.

The results over the next six months amazed Spring.

“We thought they’d do it while we were paying them, but the minute we stopped they’d go back to their bad habits,” she said. “But they continued to maintain a large improvement in their health behaviors.”

About 86 percent of participants said once they made the change, they tried to maintain it.

From baseline to the end of treatment to the end of the six-month follow-up, the average servings of fruit/vegetables changed from 1.2 to 5.5 to 2.9; average minutes per day of sedentary leisure went from 219.2 to 89.3 to 125.7; and daily calories from saturated fat from 12 percent to 9.4 percent to 9.9 percent.

The research is supported by the following National Institutes of Health grants: National Institute of Heart, Lung and Blood grant HL075451; the Robert H. Lurie Comprehensive Cancer Center of Northwestern University grant from the National Cancer Institute P30 CA060553; the National Institute of Mental Health grant F31 MH070107.