Cacioppo’s work examines the biological context
of the extended social structures that are characteristic of the human species, with a focus on perceived social isolation, or loneliness.
His research integrates many levels of inquiry, from genetics to psychology to epidemiology.
He described how loneliness has a comprehensive set of negative health effects if it persists over time.
Loneliness over the long term can lead to depression, for example. In addition, loneliness
that lasts at least 3 years also conveys cardiovascular
dangers, he discovered. A study of Chicagoans found that the average blood pressure
of the least lonely people was 0.6 mm/Hg lower than others’. “This is equal to the effect of statins,” the cholesterol-lowering prescription medication, said Cacioppo.
Cacioppo’s work with his colleagues has uncovered some of the ways that people’s bodies respond to perceived social isolation by preparing
them for life without contact with others. For example, they found that people who felt lonely had more “microawakenings” throughout
the night. In contrast, sleep is sound in the communal Hutterite society, which has an “overall loneliness lower than any other population
in the world that we’ve measured,” Cacioppo
said.
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Cacioppo (l) accepts the Matilda White Riley Lecture Award from Dr. Robert Kaplan, director of NIH’s Office of Behavioral and Social Sciences Research. |
“If it’s hard to survive standing alone with a stick in your hand to defend against wild beasts, think how much more dangerous it is to lay that stick down at night to get some sleep when predators are out and you don’t have safe social surroundings,” said Cacioppo.
His team’s research has also demonstrated
that there are about 200 changes in gene expression in people who are very lonely.
Some of these are involved in the stress response and others are part of the immune system. These immune changes strengthen the body’s response to bacteria, which are present throughout the environment, while sacrificing
immunity to viruses, which are primarily spread from person to person.
Loneliness isn’t all bad, Cacioppo emphasized. In fact, feeling lonely is an important trigger that encourages our species to stay in groups, which is our best bet for our own and our children’s
survival. Loneliness can feel awful so we seek to reduce that unpleasant feeling by reconnecting
with our group.
Cacioppo said that our species needs to have some people who don’t get lonely easily. “We need explorers who are going to go over that next hill, like Lewis and Clark,” he said. Humanity needs loneliness-prone people, too, who will stay at home with their families and protect the group against threats while the explorers are away.
Cacioppo is the Tiffany and Margaret Blake distinguished
service professor at the University of Chicago and director of the university’s Center for Cognitive and Social Neuroscience. He and his colleagues are now working with the U.S. Army on interventions for soldiers’ loneliness.
“If we succeed,” he said, “we’ll translate the intervention into older adults,” who can bear a heavy burden of loneliness and its consequences.
“That’s our ultimate goal.” 
