A supportive marriage has long been associated with numerous health benefits, including lower risks of heart attack and longer lives. But when it comes to weight gain, previous research has shown that married couples have a harder time avoiding weight gain.

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A new study recently published in the journal Health Psychology, however, has some good news for couples: Supportive partnerships may help keep your weight down.

For the new research, scientists used data on 2,636 adults  from the Midlife in the United States study who participated in two waves of data collection 10 years apart.

The participants were either married or in long-term relationships and self-reported their marital quality throughout the study.

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For a nine-year follow-up period, researchers noted the adults’ responses and tracked their weight gain. Numerical values were added to their relationships based on the responses. They ultimately found that those with high levels of marriage quality and support were less likely than people with lower levels of marriage quality and support to gain weight over time.

One step up on the marriage quality scale revealed a three-quarter of a pound drop in approximate weight. One step up on the support scale translated to about 1.5 fewer pounds gained and a 22 percent lower risk of obesity.

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"This study suggests a supportive marital relationship is associated with healthier body weight in midlife. It adds to the evidence that a positive social relationship is a health asset," study co-author Ying Chen told Time, adding that those in supportive long-term relationships are more likely to encourage healthy behaviors in each other.

But interestingly, marital strain didn’t seem to significantly affect weight gain at all.

“It is possible that middle-aged couples have stayed in the marital relationship for a longer time and may have developed effective strategies to cope with negative marital experiences,” she said. “Another possibility is that because this study only included participants who were married or in a marriage-like relationship when assessed in mid-life, those in stressful marital relationships may have ended their marriage in earlier life and were thus not eligible to be in our sample.”

Still, you don’t have to be married or even in a committed relationship to reap similar health benefits. The new research, Chen said, shows that greater social interaction and social support in general may improve health and well-being.

Read the full study at psychnet.apa.org.