The more social ties people have at an early age, the better their health is at the beginnings and ends of their lives, a new study suggests.
Researchers say the study is the first to definitively link social relationships with concrete measures of physical well-being such as abdominal obesity, inflammation, and high blood pressure, all of which are associated with long-term health problems, including heart disease, stroke, and cancer.
“Based on these findings, it should be as important to encourage adolescents and young adults to build broad social relationships and social skills for interacting with others as it is to eat healthy and be physically active,” says Kathleen Mullan Harris, professor at the University of North Carolina at Chapel Hill.
The study builds on previous research that shows that aging adults live longer if they have more social connections. The new study not only provides new insights into the biological mechanisms that prolong life but also shows how social relationships reduce health risk in each stage of life.
Specifically, the findings show that the sheer size of a person’s social network is important for health in early and late adulthood. In adolescence, that is, social isolation increases risk of inflammation by the same amount as physical inactivity—and social integration protects against abdominal obesity.
In old age, social isolation is actually more harmful to health than diabetes on developing and controlling hypertension.
In middle adulthood, it isn’t the number of social connections that matter, but what those connections provide in terms of social support or strain.
“The relationship between health and the degree to which people are integrated in large social networks is strongest at the beginning and at the end of life, and not so important in middle adulthood, when the quality, not the quantity, of social relationships matters,” Harris says.
For the study, published in the Proceedings of the National Academy of Sciences, researchers drew on data from four nationally representative surveys of the US population that, together, covered the lifespan from adolescence to old age. They evaluated three dimensions of social relationships: social integration, social support, and social strain.
They then studied how individual’s social relationships were associated with four markers shown to be key markers for mortality risk: blood pressure, waist circumference, body mass index, and circulating levels of C-reactive protein, which is a measure of systemic inflammation.
One of the four nationally representative surveys was part of the National Longitudinal Study of Adolescent to Adult Health, or Add Health, the largest, most comprehensive data researchers use to study how social relationships, behavior, environment and biology interact to shape health in adolescence and influence well-being throughout adulthood.
“Our analysis makes it clear that doctors, clinicians, and other health workers should redouble their efforts to help the public understand how important strong social bonds are throughout the course of all of our lives,” says Professor Yang Claire Yang.
The National Institutes of Health and the University Cancer Research Fund at UNC Lineberger funded the study.