"Now is the time to make New Year's resolutions to quit smoking, take exercise, or lose weight. And doing it with your partner increases your chances of success," said Sarah Jackson, lead author from University College London.
The team found that among women who smoked, 50 percent managed to quit if their partner gave up smoking too at the same time. Men were equally affected by their partners and were more likely to quit smoking, get active, or lose weight if their partner made the same behaviour change.
For the study, the team looked at 3,722 couples, either married or living together and over age 50."Making lifestyle changes can make a big difference to our health and cancer risk. When couples make those changes together, they are more likely to succeed," added Julie Sharp, Cancer Research UK's head of health information.
Getting some support can help people take up good habits. For example, if you want to lose weight and have a friend or colleague who's trying to do the same thing you could encourage each other by joining up for a run or a swim at lunchtime or after work, the authors said.
Unhealthy lifestyles are a leading cause of death from chronic disease worldwide. The key lifestyle risks are smoking, excess weight, physical inactivity, poor diet, and alcohol consumption. The research appeared in the journal JAMA Internal Medicine.