Julianne Holt-Lundstad’s forthcoming review in the 2018 Annual Review of Psychology mines the existing body of literature on social connection and physical health. Holt-Lundstad, a Psychology professor at Brigham Young University, argues that social isolation, like obesity, is a “multiply determined” health risk factor, and as such must be approached as a public health issue. Regarding the essential role of social connection in human health and survival, Holt-Lunstad writes:
“Humans are one of the most vulnerable species at birth, relying on others for nearly all aspects of survival—a human infant would simply die if left alone…it is…clear that humans would not survive without the care and nurturance of others…”
“Much as thirst drives one to consume water, loneliness may be a biologically adaptive response motivating one to reconnect socially.”
Holt-Lundstad has previously advocated for making social connection a public health priority at the American Psychological Association’s 2017 convention, as well as in a recent article in the American Psychologist. In her forthcoming paper, Holt-Lunstad undertakes an extensive review of the literature on social connection’s links to physical health and longevity.
As she explains, research using a variety of measurement methods has plainly shown that “those who are more socially connected live longer.” Other research highlighted in the review includes findings that showed links between social integration and decreased risk for “physiological dysregulation” in early and later stages of life, and evidence that social isolation is a risk factor for mortality to the same or greater degree as obesity.
Holt-Lundstad uses a systems approach to both understand the factors that underlie the link between social relationships and health and to underscore the need to move social connection into the arena of public health. As she explains, systems models view individuals in the context of family and close relationships, community, and society, and see these levels as being interrelated.
Holt-Lunstad’s review includes research findings that focus on each of these levels. The field of psychology has traditionally examined individual-level factors related to social connection, such as genetics and personality. Relationship-level research has reviewed attachment, early childhood experiences, and social control (e.g., efforts to change a partner’s behavior).
In her overview of community-level research, Holt-Lundstad highlights a series of well-known studies by Christakis and Fowler in which they used large, longitudinal data sets to identify clusters of 15 distinct physical and psychological health behaviors within social networks, including smoking, obesity, heavy drinking, happiness, loneliness, and cooperation.
Furthermore, the researchers found that these effects occurred across three degrees of relationships. Despite this phenomenon’s significant implications for public health interventions, its cause is unknown and could be attributable to various factors, including peer selection effects (people’s tendency to associate with those who are similar to them) or contagion.
Regarding society-level factors that affect protection or risk, Holt-Lundstad discusses norms regarding ideal levels of social engagement, as well as cultural values that emphasize independence versus interdependence. She notes recent U.S. demographic trends that point to a strong cultural emphasis on independence, such as the fact that greater numbers of people now live alone, and fewer are getting married and having children.
“Societies that value independence, and communities that support it, may be doing so at the detriment of long-term health.”
Holt-Lundstad argues that future social connection-related interventions must move beyond the one-on-one to act on relationship, community, and society levels. She highlights examples of ongoing community-level projects such as the Blue Zones Project and anti-bullying school initiatives.
At the society level, she argues for the implementation of interventions aimed at changing societal norms that prize independence over connection, such as media campaigns and “subtle messaging” in movies and television. Although Holt-Lundstat acknowledges that such norms are deeply entrenched and therefore challenging to change, she points to shifts in attitudes towards smoking in the U.S. and significant reductions in the number of smokers in the last several decades (15.1% of US adults as of 2016, compared to 42.4% in 1965) as a model of what is possible.
“Could a shift in our social norms and attitudes from independence toward interdependence and connection lead to a reduction in health risks similar to the shifts seen in the case of smoking?”
Holt-Lundstad also suggests specific social policies that could serve to cultivate greater social connection, including mandating paid parental leave in order foster connection at sensitive stages of life, tax incentives for those living with or caring for an aging family member, and government-supported, research-based guidelines on social activity, much like those on exercise and nutrition.
In closing, Holt-Lundstad cautions against intervening only with those at high risk of social isolation, as has typically been the case, as doing so may add to the stigmatization of loneliness and isolation. The link between social connection and health is not just a matter of extremes, Holt-Lundstad explains; rather, it has implications for all of us and should be made the focus of prevention efforts. “We all can benefit from establishing and maintaining healthy social relationships,” she writes.
Holt-Lunstad, J. (2017). Why social relationships are important for physical health: A systems approach to understanding and modifying risk and protection. Annual Review of Psychology, 69(21), 21.1-21.22. Advance online publication. https://doi.org/10.1146/annurev-psych-122216-011902 (Link)