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In Sickness and In Health

Before you say, "I do," scrutinize your lover's drinking habits. Or eating patterns. Your choice of romantic partner helps determine how healthy—or how sick—you'll be.

It definitely has its delights, but falling in love shakes up your life quite a bit. Devoting yourself to a partner includes taking on new friends, new relatives, and a new living arrangement. Pairing up also sparks sweet dreams about the goals you'd like to reach, trips you want to take together, kids you hope to have...

Likely, the last thing on your mind is how your beloved will tweak your cholesterol levels. Yet, a large body of research shows that relationships steer our physical well-being as well as our emotional health. A romantic partner often has more influence on our behaviors than anyone else. Exactly how he or she affects our health is sometimes common sense (if not obvious) and sometimes as mysterious as love itself.

We tend to hook up with people like us. "Everyone says opposites attract, but opposites don't stay together for that long," says Deanna Meyler, who co-authored a review of research on the tendency of partners' health habits and statuses to merge, a phenomenon known as health concordance. Sustained relationships tend to occur among people who have comparable backgrounds, attitudes, and behaviors—qualities that often find their way into one's physical condition.

Lifestyle like-mindedness is part of what drew Kelly McMasters, 32, to her now-husband, Mark Milroy, 40, back in October of 2000. She's a writer. He's a painter. When they met, both were self-employed. Both smoked. "A lot of our early courtship was going out to bars and diners," says Kelly. "We drank lots of coffee and ate lots of cheese. We didn't worry about it because we weren't seeing the effects on the outside. Little did we know what it was doing to our blood."

When two people marry, their habits become even more alike. A study of newlyweds found that each individual's health behaviors before marriage affected those same behaviors in their partner in the years after the wedding. Eating isn't the only ritual that synchs up. Researchers have found that spouses influence each others' exercise habits, doctor visits, and use of alcohol, cigarettes, and marijuana.

Soul mates can even develop the same afflictions over time—a condition in one spouse often places the other at increased risk for the same disorder. This may be true for cancer, stroke, arthritis, hypertension, asthma, depression, and peptic ulcer disease. One study shows that a person's hypertension risk doubles when their spouse is diagnosed as hypertensive.

That's probably because commitment typically leads to shared meals, activity patterns, financial resources, and social networks. Couples may also find themselves true partners in health by means of social control, in which one spouse tries to keep the other wholesome, and mood contagion, where one partner's anxiety washes over the other and even takes a toll on his or her body: Men whose wives are upset by their work are nearly three times more likely to develop heart disease.

"Individuals don't live in a vacuum," says Gregory Homish, an epidemiologist at the State University of New York at Buffalo, who conducted the newlywed study. "Everyone who's in a relationship should be aware that they're making some physically relevant decisions based on their partner's influence," he says. Our doctors should be noting it too. "They'll ask about your family history, but not about your spouse," Homish says. As a result, they might end up missing obvious risk factors for disease.

Sid + Nancy

While some research shows that marriage is good for well-being, there are many ways in which it can have the opposite effect. It's not uncommon for lovebirds to trade vices such as smoking, drinking, and drug use. "They often serve some adaptive function for the relationship," says Michael Rohrbaugh, a professor of family studies at the University of Arizona. "We'll hear, 'We have our best talks, or good sex, when we smoke together.'" Rohrbaugh believes that addiction interventions including both partners are much more likely to succeed than individual counseling sessions.

You may feel betrayed if your partner wants to drop your shared illicit pleasure, and you may take out your frustration in passive-aggressive ways since it would be taboo to directly discourage his robust goal. "The dynamics are sometimes covert," says Rohrbaugh, "and the cessation effort in such cases usually doesn't succeed."Leaving open packs of cigarettes around the house could easily break your partner's resolve to quit.

On the other hand, if your man keeps lighting up or downing pints of Ben and Jerry's, you could pay a price, too. A study of Korean women found significantly higher risks of lung cancer and breast cancer among those whose husbands smoked, most likely from the effects of secondhand smoke. And wives of men with heart disease are more likely than other women to have cardiac risk factors.

There are even sneakier forces at work between partners. Think of a wife kept awake by a husband's insomnia, or a guy whose girlfriend noisily leaves for work at 6 a.m., robbing him of his morning rest. "Sleep problems can screw up a person's physical and psychological well-being even more than eating and exercise," says Barry McCarthy, a couples therapist and a psychology professor at American University in Washington, D.C.

The tone of your love nest factors into your medical status, too. Women in marriages full of hostility have more coronary artery disease than those in warmer relationships, while men in more controlling relationships (whether they are the dominator or the one getting bossed around) have more coronary artery disease than those in egalitarian marriages. Both situations likely activate stress responses, which are known to contribute to, if not cause, an array of ailments.

Similarly, marital conflict and strain are associated with heart disease and mortality risk. For example, women who "self-silence" during arguments with their spouses are four times more likely to die over a 10-year period than their peers who express themselves. These women (23 percent of the wives studied!) may be bottling up anger out of fear of the husband's reaction. But suppressing feelings clearly has a negative effect on physiology, probably akin to stress damage, though the exact pathway isn't yet known.

Marital Sway

The good news is, you can influence your beloved's health just by changing your own behavior. Jody Sindelar, a professor at Yale School of Public Health, co-authored a study of 6,012 people over a course of 4 years. "In every single behavior we looked at, there was a big spousal effect."

If one spouse quit smoking, the other was six to eight times more likely to swear off cigarettes, too. If one gave up alcohol, the other was five times more likely to stop drinking. And if one got a flu shot or a cholesterol screening, chances were the other would, too. Contrary to what you might imagine, these effects aren't necessarily the result of a conscientious wife needling her husband; men had as much influence on women as women had on men.

Exercise, interestingly, turns out to be the exception, in that one spouse's lacing up the tennis shoes had a much milder influence on the other's tendency to do so. Sindelar explains that out of all the practices studied, getting in shape takes the most effort. You've got to muster your own willpower to get on the treadmill, no matter how pleasingly toned your honey is getting.

Positive lifestyle changes arise when one partner talks up salubrious actions to the other or simply creates a conducive environment, such as when Nettie Hartsock's husband, Andrew, quit his IT job to become a gym teacher and Pilates instructor.

Raising two kids and working a full-time job, Nettie hadn't exercised in years, but she tried out a few of her husband's classes and became a Pilates aficionado herself, practicing it about three times per week. "I have more energy and I'm less moody," she says, and he appreciates the companionship. "Having a regular activity to do together is really nice," he says.

Some pairs may even successfully attenuate the risks for physical maladies by attending couples therapy for other reasons. The therapy may have a beneficial effect on hostile or controlling behaviors, or stress-prone dispositions that undermine the health of one or both partners.

Nagging a sweetheart to alter her temperament or her bad habits, though, does not work, and can have the opposite of its intended effect: "The spouse is trying to be helpful—they don't want their partner to die! But the more they demand change, the less the other person is likely to change," explains Rohrbaugh. "Don't yell at your overweight spouse, but say, 'Let's go for a walk together,'" says McCarthy.

Even if you can't get your mate on board for therapy, you can adjust your mind-set, says Smith. "Find a way to not let them get under your skin." Not getting worked up each time she leaves the table for a cigarette break will lighten your mood, and may paradoxically push her to clean up her act. Hold your tongue for a week, and you may be pleasantly surprised.

Loving a Health Nut

Sometimes a spouse goes all out in his quest for a sound body, leaving his love behind. "My wife isn't as into fitness as I am and that's fine," says jock Andrew Hartsock. "I'm not going to go on a 50 to 100 mile bike ride with her, but we can ride around the neighborhood. We can still enjoy the activity together even without being on the same level." But compromise is not always so easy for the hyper-healthy and their sweethearts.

When 32-year-old Antima Sadhukhan's live-in boyfriend of 10 years adopted a raw-food diet, their relationship suffered. "I tried raw food, too, but I couldn't stand the taste and I felt horrible. I couldn't peel myself out of bed," she says. "Meanwhile, Alex was like the Energizer bunny."

Sadhukhan went back to cooked cuisine, and she and Alex, who always used to eat together, often at restaurants, started dining separately. "He'll eat before he leaves work and I'll eat before he gets home," she says. It's not a perfect solution. "At first, we argued about it a lot. I couldn't understand why this raw diet was so important, and I'd get offended when he wouldn't taste what I cooked," she says.

"One of the most dangerous things to say is, 'If you loved me, you would do this,'" says McCarthy. It sets up an unnecessary contingency. A better approach is to state your feelings and make a request that your partner can accept, modify, or say no to, without fearing it is a test of love.

Sadhukhan admits that though she'll never be able to completely adopt Alex's hard-core ways, a few filtered-down effects are appreciated: She's lost weight, and when she craves a snack, she reaches for the nuts and fruits he keeps in their kitchen, instead of junkier fare.

Hale and Not Hearty

While couples who thrive or suffer together grow closer, those who experience a divergence in health might fall apart. Health-mismatched pairs are more likely to get divorced than couples whose health is similar, whether good or bad. The risk of divorce is greatest for those who were happiest before the disparity emerged. Among couples battling a chronic disease, the partner in better condition typically reports greater personal life strain, worse social relations, and increased financial burden.

When Wendy Percoulis was diagnosed with breast cancer at age 33, she immediately stopped chatting with her partner, Dolly Miconi, about the tomatoes growing in their garden and where they'd take their next vacation. Instead, they talked mastectomies, and chemo appointments, and how they'd get by financially. "It put a humongous strain on us," says Percoulis.

Miconi accompanied Percoulis to all of her medical appointments and missed work to help her when chemo hit her hardest. She also took on all of the couple's day-to-day responsibilities. Percoulis battled depression and eventually had a nervous breakdown. Miconi struggled with her own moods, too.

"Once you have cancer, you change," says Percoulis. "Dolly was kind of mad that I wasn't the same person she'd met." But the two have worked through their difficulties and are now planning a trip together.

"Accept and adapt," may be the best advice for a couple confronted with a disparity. "In good relationships, people don't blame each other—'This is your fault, you should have quit smoking five years ago,'" says McCarthy. "They say, 'we can get through this one step at a time.'"

Dual Diagnosis

Almost every couple will face a medical crisis eventually. If you get the unlucky diagnosis, start by clarifying your needs, suggests Gina Artioli, 22, whose boyfriend of two years left her shortly after she got Hodgkin's lymphoma. "I didn't know how to tell him what I wanted, and he didn't know how to ask," she says.

Her brush with cancer changed her dating criteria. "I go out with friends and we see the college boys partying. I don't think they could handle my history," she says. Even when she did find a guy sensitive enough to deal with her past, their relationship got rocky when he bought a motorcycle. "I would not get on it," says Artioli. "I've had my life-threatening experience, and I don't need to have any more."

Catastrophes aren't any easier when they strike more established unions. Five days before his wedding, the man who fell in love with a fellow bar-and-diner lover, Mark Milroy, got chest pain and his arms went numb. "His symptoms were classic," says his wife, Kelly McMasters. They called paramedics, but skipped the trip to the hospital, convinced that it was nothing more than prenuptial panic. But five months later, doctors confirmed that Mark had had a heart attack—and was in the middle of a second. Emergency surgery ensued, followed by a drastic lifestyle change.

"We came home and pinned the nutritionist's recommendations to the fridge, and I started cooking for the first time in my life. It was the only way I felt I could help," says Kelly. "We eat almost every meal at home now."

Just as important as Kelly's wholesale lifestyle change to benefit her husband's well-being is her perspective. "We call it communal coping," says Rohrbaugh. "It's not his problem or her problem, it's our problem." Rohrbaugh has found that "we-talk" by a spouse predicted positive change in a patient's condition over the next six months.

Addressing the problem head-on can benefit the well spouse, too. Since swearing off cigarettes and replacing pizza and cheeseburgers with grilled vegetables and lean chicken, Kelly has lost weight and reduced her own chances of developing heart disease.

Making Good on Vows

Serious illness often turns one partner into a caregiver, and while many people describe this role as rewarding, it's also demanding—and dangerous to the caregiver's health. Depression is common. One study found that women who nursed an ill or disabled spouse for nine or more hours per week had a higher risk of coronary artery disease, probably because they were stressed by time constraints, financial burdens, and the difficulty of seeing their loved ones suffer.

That's not even the worst of it. Caregiving spouses who experience strain have a 63 percent higher overall death risk, compared to non-caregiving controls. The risks can persist even after the loved one dies. It's not unusual for people in very close relationships to die within a short time of one another. "You see people developing cancer or chronic illness about 18 months after losing someone very significant," says Laura Young, who spent 10 years as a rehabilitation psychotherapist. She couldn't escape her knowledge when she met Michael, a charming quadriplegic man, 18 years ago.

"We had an instant crush," she says. The two flirted and became close friends, but Young went on to marry another man. "One day, Michael and I discussed why he hadn't wheeled me off my feet when he had the chance. I realized he had made the decision to spare me the intensity of his needs. I don't think I could have handled it," she confesses. "It would have been extremely easy for me to fall into the caregiver role and not even realize I had let my life be subsumed by someone else's needs."

Of course, already committed couples don't have the same choice. "There's a lot of very difficult territory to negotiate when one spouse gets ill or injured," says Young. "The healthy spouse must figure out, 'To what degree am I obligated to adopt your disability?'" Open communication, allowing for psychological adjustment, and a sense of humor are critical.

Just ask Kelly McMasters—the ex-smoker and cheese-eater whose husband suffered his second heart attack months after their wedding. "If you had asked me before this went down, I would have said I didn't have a caretaking bone in my body," she says. "The last time my parents visited us, they stared at me as if I were an alien child: 'When did you learn to cook?!'"