People in Relationships Gain Weight Because They Don't Care About Their Looks

Being in a relationship is good for your health but bad for your waistline. New research from Australia revealed that, despite being healthier overall, individuals in relationships tend to weigh more than their single counterparts.

The study, published last month in the PLOS One, is based on data from 15,001 Australian adults taken from annual surveys conducted between 2005 and 2014. The participants were an average age of 52.9 years old and were equally split between men and women. Seventy-four percent were in a relationship at the time of the surveys.

The surveys were designed to look at all aspects of the individuals' health, including their lifestyle choices as well as their weight.

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Many couples may use food as part of their time together, such as the couple above sharing an ice cream treat. Peter Parks/AFP/Getty Images

Results revealed that individuals in a relationship were more likely to have healthier lifestyles than singles. Those in relationships drank less, smoked less, and ate less fast food and more fruits and vegetables than singles, New Scientist reported. However, couples seemed to do the same amount of physical activity and watched similar amounts of television as single people.

Yet couples tended to weigh more.

Catherine Hankey, a health professor at Glasgow University who previously studied weight gain in newlyweds, told Newsweek that there are likely that a number of factors are at work.

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"I think that the obvious explanations are you are no longer single and that perhaps may make keeping weight off less important," said Hankey. "It may be that couples use food and alcohol as part of their time together and treats become more common."

Armando "Dr. Mondo" Gonzalez, a licensed therapist who specializes in weight loss and obesity, and worked with contestants on NBC's The Biggest Loser, agreed with this explanation.

"A lot of people are motivated to be healthy and to look better in order to get a partner and end up in relationships," Gonzalez told Newsweek. Once singles get paired up, a lot of this motivation to look fit disappears.

Of course, this doesn't mean that all couples are destined to gain weight. Gonzalez explained that avoiding weight gain in a relationship requires re-prioritizing your reasons for getting fit. This involves shifting weight loss goals from short term, such as looking good for bikini season, to long term goals like being able to travel with your loved one in old age.

Ultimately, Gonzalez explains that couples who lose weight and keep it off together are really at an advantage.

"Two are better than one," said Gonzalez. "If couples are both on the same page, they can be in the minority of people in a relationship who do not gain weight."