Moving in with your partner could benefit your health in 3 key ways

Most romantic relationships chart the same course. You meet, you date, you get serious, and then you reach a crucial milestone: You move in together. For some, the idea of cohabiting — whether they love their partner or not — is as terrifying as it is exciting. Making the leap is fraught with uncertainty. There’s the financial details, the Craigslist ads, the existential wonderings, and the late-night Google searches to contend with. Moving in together will change you. The question is how?

Science to the rescue.

Geoffrey Leggat, a graduate student at Australia’s La Trobe University, tells Inverse that no matter how close you feel to your partner, living together means you will influence one another in new ways. That’s largely because people who live together are just around one another far more than those who don’t.

“Social theory suggests that the closer someone is to us, the more their behavior can influence us,” he tells Inverse. “Union formations, such as marriage and cohabitation, are seen as key stages of life and can contribute to a wide range of changes in lifestyle.”

These changes in lifestyle may be some of the best things that ever happened to you — and we don’t just mean psychologically. Taking the plunge and shacking up could benefit your health in unexpected ways. Fortunately, partners tend to raise one another’s mental and physical health game, though there could be some potential pitfalls to living together, too.

The health benefits of moving in together

• Someone will be watching over you.

Historically, married people have better physical and mental health than their forever-single counterparts. People who live together also reap those rewards, Arielle Kuperberg, a sociologist at the University of North Carolina, says.

"You have someone living with you, watching what you do all the time."

“People who cohabitate are healthier than single people but a little bit less healthy than married people,” Kuperberg tells Inverse. “But the differences between cohabitors and married people tend to disappear when you account for things like education, wealth, income.”

Living with someone else raises the stakes on the consequences of your behavior, she says. Basically, there’s always someone around the house. If that person is your romantic partner, they would (presumably) like to see you stay alive and healthy for as long as possible.

“One of the reasons marriage is associated with better health behavior is because you have someone living with you, watching what you do all the time,” she says. “You’re getting the monitoring whether you’re married or not.”

This might discourage unhealthy behaviors, like eating poorly or smoking, she says. But there’s also evidence that cohabitation can help boost good behaviors, too.

• You could hit the gym more

One such benefit is that living together might help you stick to the gym. A 2017 study found that couples who attend exercise classes together are more likely to keep going to them compared to non-couple groups.

The benefits of taking regular exercise on your physical health are too exhaustive to list here, but to give a taste, a new study out this week suggests that exercise can help prevent prostate cancer. And conversely, research suggests that not being physically active — even for a short period of time — can take a surprising toll on your physical health.

Getting active can also benefit your mental health. A study published in November 2019 found that exercising for the right amount of time each week could protect against depression.

• You might drink less — if you are a man.

In a new study, published this week, Leggat and his colleagues show that cohabiting heterosexual couples impact each other’s alcohol consumption.

The women in this study drank less than their male partners on average to begin with. As time went on, their male partners started to drink less alcohol, too, while the women’s consumption stayed pretty consistent over time.

By accounting for other factors that can impact drinking during a relationship, the researchers found that the men’s changing habits were largely influenced by their female partners’, suggesting that the women’s drinking habits really were the force of change in their lives.

Surprisingly, the same did not hold true for men — their drinking habits don’t seem to have as much influence on their female partners, the researchers find.

But though moving in may benefit you in these three key ways, it can also come with potential risks.

How cohabitation negatively impacts health

• You could drink more — if you are a man.

Take drinking too much. The same study that suggests men who live with a female partner may end up drinking less if that partner drank less to start with also suggests that the opposite might occur.

The main effect the researchers found was that female partners exert significant influence over their male partner’s drinking habits. That suggests that if a woman drinks too much upon moving in with a male partner, he could end up increasing his alcohol consumption, too.

Leggat chalks this possible outcome up to a few things. If one partner drinks, there’s likely to be more alcohol around the house, and there may be an element of social pressure involved.

“Partners living together may find themselves accompanying their partner in social spaces or activities more often, providing them more chance to engage in similar drinking behavior, especially if one partner is a heavier drinker,” he says.

It’s important to consider the negative affects of a partner’s influence on alcohol intake for treating problem drinking, Leggat and his team argue. If you are living with someone, seeking treatment for yourself may not be enough — your partner may have to sign up for greater sobriety, too.

• You might gain weight.

The same effect seen for drinking can be seen in food, too. Partners’ habits — and their future choices — influence one another.

A 2016 study on 215 families found that the way one partner eats often influences the way the other does, too. That applies if one partner eats poorly. For example, one person’s fast food consumption was correlated with the other’s fast food consumption. But that also worked for healthy eating habits, too: For every standard deviation increase in produce consumption in one partner, the other partner’s produce consumption increased 20 percent. So it might not be all bad — if your partner was a healthy eater to start with.

The result jibes with past research. A 2011 paper found that couples’ eating habits tend to be concordant. In that study, the researchers analyzed the food consumption habits of 3,000 people. They then placed them into categories based on what they tended to consume most, from people who had “healthier” eating patterns to those who thrived on “alcohol and snacks,” or “meat and soda.”

Partners are far more likely to belong to the same category. If a spouse primarily ate meat and soda, their partner was 5.9 times less likely to be in the healthier-eating category.

They also found evidence that one partner’s eating habits are predictive of the other’s future eating habits, too — again, both good and bad. For example, if one partner’s eating patterns fell into the “meat and soda,” “alcohol and snacks,” or “healthier” category, their partner was likely to eat that way in the future.

But how cohabitation affects weight is unclear. A 2018 paper found that living together leads to significant weight gain in both men and women after about four years together — but the same wasn’t true if they got hitched. Cohabiting partners’ increase in weight gain was twice the amount seen in married couples. But what, exactly, being married changes about the trend is unknown.

"Marriage and cohabitation are seen as key stages of life and can contribute to a wide range of changes in lifestyle."

The overall verdict

Ultimately, the researchers agree that social ties can promote healthier habits — and that people should try to take advantage of them.

“Changes in behavior appear to apply, not only to drinking, but for many different facets of life, such as smoking or exercise,” says Leggat. “Stronger and better quality relationships provide better support and can lead to better health outcomes.”

Health habits often run in social circles. It may be possible to predict a person’s health, stress levels, or happiness just by looking at the health of their friends, according to a 2019 study.

“Imagine the context of having a gym buddy or group,” lead study author Nitesh Chawla told Inverse at the time. “There is that support, that understanding, that motivation, and that perception of self and others that helps us develop that social network support.”

Taken together, the research on cohabitation suggests that the same social ties that drive bad behavior can drive healthy behavior, too.

So if you are in a close relationship and thinking about taking a next step, rest assured that, if nothing else, moving in together could help you kick that bad habit your partner finds so irritating … but be careful not to pick up a worse one.