Psychologists’ research has long established that relationships have the power to influence physical and mental health, for better or worse. Now, new research is expanding our understanding of the ways that relationships influence such conditions as cancer, heart disease, depression and addiction. That evidence is leading psychologists to say that strengthening those bonds should be a public health priority.

It’s not an exaggeration to say that lack of social connections can be deadly. Strong social relationships increase the likelihood of survival by 50 percent regardless of age, sex or health status, according to a meta-analysis of 148 studies on mortality risk by Julianne Holt-Lunstad, PhD, of Brigham Young University, and colleagues (PLOS Medicine, Vol. 7, No. 7, 2010). They found social disconnection is at least as harm-ful to people as such well-accepted risk factors as obesity, physical inactivity and smoking up to 15 cigarettes a day.

And a lack of social companionship is a widespread problem. In the United States, 20 percent to 43 percent of adults over age 60 experience frequent or intense loneliness, according to a study by Carla Perissinotto, MD, and colleagues (Archives of Internal Medicine, Vol. 172, No. 14, 2012). Some 30 percent of U.S. married couples report severely discordant relationships, as Mark Whisman, PhD, and colleagues found (Journal of Consulting and Clinical Psychology, Vol. 76, No. 5, 2008). And the size of the average American’s core social network has declined on average by a third since 1985, according to the Pew Research Center (Social Isolation and New Technology, 2009).

Still, loneliness and social ­isolation are rarely featured in public health campaigns, psychologists say. “I don’t think there is widespread acknowledgement of this as an important health issue, either by major health organizations or by the general public,” Holt-Lunstad says.

That’s a missed opportunity since research also suggests that the sooner society takes steps to address social isolation, the better. Holt-Lunstad and colleagues emphasize the importance of raising awareness of the effects of relationships on well-being in “Close Family Relationships and Health,” a special issue of American Psychologist, (Vol. 72, No. 6, 2017) that reviews the existing literature and provides new analyses to move the field forward. Here, we explore the special issue—and where the field is headed next.

Pathways that link close relationships and health

Paula Pietromonaco, PhD, a social psychologist at the University of Massachusetts, Amherst, and Nancy Collins, PhD, at the University of California, Santa Barbara, lay out a theoretical framework detailing the interpersonal processes and intrapersonal pathways that link relationships to physical health.

Social connection (or disconnection) can affect health through biological pathways such as immune function or the regulation of stress hormones. Relationship quality can affect health by influencing psychosocial factors such as mood, motivation and coping skills. Friends and family members can also influence a person’s health-­related behaviors such as eating and exercise habits. Together, those pathways can have long-term outcomes for physical and psychological health. 

More research is needed to flesh out the fine points of these pathways, the authors agree. However, they add, the theoretical foundation is sturdy enough to start building solutions for healthy relationships.

Investment in healthy relationships is particularly important as the population grows older and sicker, especially given serious concerns about health-care cost, access and delivery, Pietromonaco says. “If we can understand how relationships might act in a preventative way, that will be important both for improving the quality of people’s lives and saving money in terms of health-care costs down the line.”

Happy childhood, healthier life

An interesting aspect of relationship research is that it is relevant to the entire lifespan, says Northwestern University psychologist Edith Chen, PhD. In the special issue, she and co-authors Gene Brody, PhD, of Emory University, and Gregory Miller, PhD, of Northwestern University, describe one end of that spectrum, focusing on the way childhood relationships influence health.

Supportive relationships in childhood can buffer children against future physical health problems, the authors say. When children experience comforting, emotionally significant relationships with parents or other close family members, they tend to have better health profiles—not only during childhood, but into adolescence and adulthood. In one longitudinal study, Linda G. Russek, PhD, showed that college students who had more caring parents had a lower risk of heart disease, ulcers and other chronic conditions 35 years later (Journal of Behavioral Medicine, Vol. 20, No. 1, 1997).

But most research on childhood family relationships takes a black-and-white view of those interactions. Studies often characterize the nature of the relationship as positive or negative, supportive or unsupportive, though the shape of parent-child relationships isn’t static, Chen says.

“Across development, children’s needs from their parents change,” she says. Parental behavior that might be described as attentive in early childhood could be seen as overbearing to a teen. Families that are highly supportive of one another might also expect more from their adolescents, creating stress related to family obligations. Understanding those shifting dynamics will be key as researchers develop interventions to support healthy relationships throughout childhood and adolescence, the authors say.

Close social ties in later life 

Close social ties in later life At the other end of the lifespan, relationships can present an entirely different set of challenges, write Karen Rook, PhD, and Susan Charles, PhD, both of the University of California, Irvine. On one hand, research paints a positive picture for older adults’ relationships, as Rook and Charles describe. Compared with younger adults, older adults report more satisfaction with their social networks. They’re often more proactive about managing their social networks, making efforts to maintain satisfying relationships while winnowing ties with more problematic friends and relatives. On the other hand, older adults might be more susceptible to loneliness and social isolation as their mobility decreases and close friends and family members pass away. They might also be more vulnerable to the negative effects of fraught relationships that they cannot avoid.

Interestingly, Rook and Charles assert that there have been few efforts to look at how proactive social management and vulnerability to social isolation and negative social interactions fit together to affect the health and well-being of older adults. “Those lines of research have largely co-existed side by side, without much effort to integrate them,” Rook says.

Creating an integrated model of older adults’ social worlds is a necessary step toward providing the social support they need to thrive, Rook adds. By 2030 more than 20 percent of the U.S. population will be over age 60, Rook and Charles note, and by some estimates more than 80 percent of them will have at least one chronic condition. In that light, the quality of older adults’ close relationships takes on particular importance for public health.

“The population is aging and, at the same time, demographic shifts in the U.S. and western Europe mean that more people are reaching old age without marrying or having children,” Rook says. “In terms of loneliness and social support for day-to-day needs, that leaves a big question mark.”

A neurochemical perspective 

Bert Uchino, PhD, at the University of Utah, and Baldwin Way, PhD, at The Ohio State University, explored the neurochemical pathways that link relationships and health. The quality of close family relationships can affect endocrine function, immune function and nervous system activity, they say. And those systems are linked to leading causes of illness and death, including cardiovascular disease, infectious diseases and cancer.

Understanding relationships at the biological level could help give a clearer picture of the ways that social connections can impair or protect one’s health, Uchino adds.

For example, Uchino and Way note that both laboratory and naturalistic studies show close family relationships are linked to favorable levels of the stress hormone cortisol, which plays a role in important functions such as glucose metabolism and immune function. The authors also make a case for the protective role of the neurochemical oxytocin, the hormone released during social bonding that has been shown to reduce blood pressure and lower cortisol levels.

Uchino hopes that more research on these mechanisms will lead to new interventions that better target a person’s underlying biology. For example, he says, future interventions might combine behavioral treatment, such as couples therapy, with pharmaceuticals, such as inhaled oxytocin. But to get to that point, he says, psychologists will need to partner with researchers in other fields and embrace new types of treatments. “It’s really hard to alter relationships. Getting people to change their patterns is difficult,” he says. “We need to think of better ways to help implement those changes.”

Intimate relationships and heart disease 

Intimate relationships and heart diseaseThe link between relationships and cardiovascular disease provides one of the clearest examples of the ways relationship quality can affect health, say Timothy Smith, PhD, and Brian R.W. Baucom, PhD, both of the University of Utah. People in secure, committed romantic relationships have a lower risk of heart disease, for example, while those who have relationship discord have a higher risk.

But other psychosocial factors also increase heart disease risk—and health researchers should consider the links between those factors in a new light, the authors say. Research shows that factors such as anger, hostility, depression, anxiety and post-traumatic stress disorder boost heart disease risk. Those elements also affect people’s social lives. “The same risk factors that put people at risk for cardiovascular disease are also very important indicators of the quality of people’s intimate relationships,” Smith says.

Smith and Baucom argue that too often, researchers consider personality factors and relationship factors in isolation. But in the real world, they say, difficult personalities and relationship troubles go hand-in-hand in ways that are likely to affect heart health. People studying personality problems should stop thinking of relationship difficulties as a confounding factor in their research, Smith says, and vice versa.

“We have to start thinking about what it means that over and over again, these two domains are so closely correlated,” he says. “What does that mean for risk—and what might we do about it?”

Since heart disease is the top cause of death worldwide, efforts to reduce risk by strengthening relationships before the disease arises could have a significant effect on public health, Smith says. “Why shouldn’t we spend a little more money teaching couples to manage common relationship difficulties, or teaching expecting parents how to do better with the stress of parenting?”

Chronic illness in the family

About half of all U.S. adults have at least one chronic illness, and 84 percent of all health-care costs are spent on their care, say Lynn Martire, PhD, at The Pennsylvania State University, and Vicki Helgeson, PhD, at Carnegie Mellon University. Close relationships take on a particular importance when someone is managing chronic health conditions.

When children have warm, supportive home environments with good family communication, they have better management of chronic illnesses such as asthma, diabetes or congenital heart conditions, Martire and Helgeson say. For adolescents and adults, however, it’s less clear how involved a family member should be. Parents of adolescents or spouses of adult patients can help encourage healthy habits. But when a person is too controlling, it can backfire and even push a patient toward unhealthy behaviors.

But what’s too controlling? “One person’s nagging might be another person’s caring,” Martire says. She suggests that the most successful interventions for chronic conditions will take a tailored approach, helping couples or other family members hit the right level of support. “Our best bet is to take evidence-based patient programs aimed at improving illness management, and see how they could be modified to include both the patient and a close family member,” Martire says. “We know a lot about behavior change, and it’s time to incorporate that into more family-based programs.”

The role of culture 

Close relationshipWhile the research leaves little doubt that relationships are important for health, there are important gaps in the literature when it comes to understanding culture and diversity, write Belinda Campos, PhD, at the University of California, Irvine, and Heejung Kim, PhD, at the University of California, Santa Barbara.

Most research on health and relationships has focused on middle-class, European-American families. But social experiences and expectations vary widely among different cultural groups, Campos and Kim note.

To European Americans, for instance, social support is thought of as a good thing. But among people of East Asian heritage, asking family members for more support might increase stress and undermine health. And while much of the research on health and relationships focuses on the quality of marital partnerships, in some cultures, people put more emphasis on their family of origin than on romantic relationships.

“We know so very little about any kind of human variation in these relationship processes,” Campos says. “The necessary next wave of this research will be understanding cultural variation.”

Building a public health intervention

Despite the lingering questions, most researchers at the intersection of health and relationships say it is past time to start designing interventions to strengthen relationships—and, by extension, improve health.

“Relationships are instrumental in our day-to-day lives and in our physical and mental health. How do we use that?” asks Christine Dunkel Schetter, PhD, a psychological scientist at the University of California, Los Angeles, who wrote the introduction to the special issue.

“We’ve learned so much, but we’re not doing so much. Somewhere we have the answer, and I think psychologists are at the center of it,” she adds.

One key to moving forward is more funding, experts agree. More research is needed to clarify the mechanisms and identify the best interventions to strengthen social connections—and demonstrate through randomized controlled trials that social interventions lead to measurable improvements in health, Uchino says. “We know that an association exists, but we need to fill in the open questions.”

Practicing clinical psychologists can also play a role, Uchino adds. “Psychologists can incorporate these research findings into their practice or wellness programs so that patients are aware of the impact their relationships have on their health.”

Holt-Lunstad is calling for experts to develop formal guidelines for social activity, similar to nutrition and exercise guidelines issued by governments and public health organizations. She also urges government agencies and health-care funders to do more.

Such institutions invest significantly in interventions to address determinants of health such as obesity and tobacco use, but healthy relationships barely register on their radar screens, she says. She has spoken to government officials in the United States and the United Kingdom to raise awareness of the proven importance of relationships to public health, and encourages her colleagues to continue to help connect those dots.

The researchers included in the special issue are by no means the only ones contributing to the science of relationships and health, Dunkel Schetter says, and she hopes the publication will inspire others working in the field to speak up and make their research known.

Moving forward will require a team approach, Dunkel Schetter adds. Scientists may have to move out of their comfort zones to connect with policymakers and public health experts and publicize their findings in the media. But she’s optimistic that her colleagues are up to the job. “Psychologists have wonderful methods, wonderful theories, lots of super intelligent people,” she says. “This shouldn’t be a nut that we can’t crack.”

New research

These articles on relationships and health appear in American Psychologist, 2017, Vol. 72, No. 6

  • Moving Research on Health and Close Relationships Forward—A Challenge and an Obligation: Introduction to the Special Issue 
    Christine Dunkel Schetter
  • Advancing Social Connection as a Public Health Priority in the United States 
    Julianne Holt-Lunstad, Theodore F. Robles and David A. Sbarra
  • Interpersonal Mechanisms Linking Close Relationships to Health 
    Paula R. Pietromonaco and Nancy L. Collins
  • Incorporating the Cultural Diversity of Family and Close Relationships Into the Study of Health 
    Belinda Campos and Heejung S. Kim
  • Childhood Close Family Relationships and Health
    Edith Chen, Gene H. Brody and Gregory E. Miller
  • Close Social Ties and Health in Later Life: Strengths and Vulnerabilities
    Karen S. Rook and Susan T. Charles
  • Intimate Relationships, Individual Adjustment, and Coronary Heart Disease: Implications of Overlapping Associations in Psychosocial Risk
    Timothy W. Smith and Brian R.W. Baucom
  • Integrative Pathways Linking Close Family Ties to Health: A Neurochemical Perspective
    Bert N. Uchino and Baldwin M. Way
  • Close Relationships and the Management of Chronic Illness: Associations and Interventions
    Lynn M. Martire and Vicki S. Helgeson