Your Friends, Not Family, Will Help You Live Longer: Study

Friends and family surround a newly naturalized citizen, center, after a naturalization ceremony in the Brooklyn borough of New York on December 15, 2015. A new study found that older participants identified friendships as predictors of how happy they felt. Lucas Jackson/Reuters

As individuals grow into adulthood, the value of their friendships has more of an impact on their health and well-being than that of their families, according to a new study.

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In two separate parts of the study, researchers at the University of Michigan sought to discover whether the link between close relationships and health and well-being are static across life, or if the benefits are most evident in older adults, when concerns about physical health are greater. The researchers asked participants about relationships, happiness and health.

For the first portion of the study, the researchers surveyed 271,053 adults and found that valuing friendships was related to better functioning, particularly among older adults. Meanwhile, valuing familial relationships "exerted a static influence on health and well-being across the lifespan," the study says.

In the second portion, a large sample of older adults was used to examine whether the effects of receiving support and strain from different relationship sources—such as spouses, children, family and friends—predicted changes in health over six years and subjective well-being (over eight years). After questioning 7,481 older adults, the study showed that only strain from friendships predicted more chronic illnesses over a six-year period. Meanwhile, support from spouses, children and friends predicted higher subjective well-being over an eight-year period.

Engaging and investing in close relationships are activities associated with a variety of psychological and physical health benefits. Previous studies have found that the quality of these relationships has been linked to healthier behavior, lower incidence of chronic illnesses, higher levels of happiness and lower mortality. Researchers typically believe that the enhancing effects of investing in close relationships are present throughout life.

The study compared the relative magnitude of the effects that different close relationships—with friends, family, spouses—have on well-being and health among younger, middle-aged and older adults. Valuing and receiving support from different types of relationships were each uniquely associated with better health and higher happiness and subjective well-being across the lifespan.

The authors say that future studies can examine which (and how) close relationships exert their influence on health and well-being and the factors (cultural, social and personal variables) that might attenuate these mechanisms.