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Weight loss may hurt relationship if only one partner sheds pounds

Losing weight can tack on quality years of life for overweight individuals, but a new study suggests it might lead to the demise of your relationship if both partners aren't all in on the transition.

"People need to be aware that weight loss can change a relationship for better or worse," said study author Dr. Lynsey Romo, an assistant professor of communication at NC State.

For her study, researchers recruited 21 couples from across the U.S., each of which had one partner who lost 30 or more pounds in less than two years. On average, most lost about 60 pounds during that time.

All participants were given questionnaires asking about how the weight loss impacted their relationship.

After weight loss, most couples said they were more communicative in a good way: The partner who lost the weight was more likely to talk about healthy living and inspire his or her partner to engage in or maintain one as well. When both partners were receptive to these healthy changes, they reported boosts in physical and emotional intimacy.

But, some partners who lost weight resorted to "nagging" their significant other to follow their lead, which the researchers say caused tension.

Others who hadn't lost weight said they felt threatened and insecure by their partner who did lose the extra pounds -- they tended to be the most resistant to change in their relationships, the researchers pointed out. Often they'd make critical comments towards their partner, lose interest in sex or try to sabotage them with unhealthy meals to prevent their relationship from changing.

Romo says her study suggests communication plays an important role in a healthy relationship. When both partners were on board with the healthier changes and support was strong, couples were brought closer together. When a partner resisted the changes or was not supportive, the relationship took a hit.

"This study should not dissuade anyone from losing excess weight, but it should encourage people to be aware of the potential pros and cons of weight loss on their relationship," she said. "It is really important for the partner of someone trying to lose weight to be supportive of their significant other without feeling threatened by their health changes. This approach will help people lose weight without jeopardizing the quality of their relationship."

The study was published Oct. 24 in Health Communication.

"We fall into these patterns with people we have relationships with," Dr. Charlotte Markey, chair of psychology at Rutgers University in New Brunswick, N.J., told HealthDay. She reviewed the study's findings. "When these patterns shift, it can be unsettling."

Markey recommended discussing any feelings of inadequacy as they arise if one partner is losing weight while one that may also need to isn't.

"Hopefully the partner will say 'Well, you shouldn't.,'' she said.