Being Lonely Is Really, Really Bad For You

Researchers have long known that loneliness can have negative health effects, from disrupted sleep to increased risk of heart disease; it also seems to be on the rise, reaching what some experts call "epidemic levels." New research, presented at the 125th Annual Convention of the American Psychological Association, suggests that loneliness and social isolation in the United States may be a greater public health threat than obesity—its effects are likely to grow as the population ages.

"Being connected to others socially is widely considered a fundamental human need—crucial to both well-being and survival. Extreme examples show infants in custodial care who lack human contact fail to thrive and often die, and indeed, social isolation or solitary confinement has been used as a form of punishment," Julianne Holt-Lunstad, professor of psychology at Brigham Young University, said in a statement. Researchers consider loneliness akin to hunger and thirst: It's an aversive cue that something is wrong. "Yet an increasing portion of the US population now experiences isolation regularly," she said.

Just how much that portion has increased remains a tricky question to answer. The most recent US census data show that more than a quarter of the population lives alone, more than half is unmarried, and the number of children per household is on the decline. John Cacioppo, who studies loneliness at the University of Chicago, cites various studies from the 1970s and 1980s suggesting that the percentage of Americans who regularly or frequently felt lonely was between 11 and 20 percent. He also points to the AARP's 2010 Loneliness Study, which found that 35 percent of Americans aged 45 or older were categorized as lonely, while his own longitudinal studies put the number at around 26 percent.

To help understand what's happening to all those lonely people, Holt-Lunstad presented data from a pair of meta-analyses; her research has not been published in a peer-reviewed journal. The first review encompassed 148 studies, including more than 300,000 participants. Greater social connection, it found, was associated with a 50 percent reduction in the risk of early death. The second study collated data from 70 studies involving more than 3.4 million participants, mostly from North America, but with some from Europe, Asia, and Australia. It found that social isolation, loneliness, and living alone (which more Americans are doing) all have significant and equal effects on the risk of premature death. In fact, the effect is on par with or greater than other risk factors such as obesity.

"There is robust evidence that social isolation and loneliness significantly increase risk for premature mortality, and the magnitude of the risk exceeds that of many leading health indicators," Holt-Lunstad said.

The challenge now is what to do about it. She suggested devoting more resources to understanding the problem, as well as emphasizing the importance of social connectedness among everyone from schoolchildren to soon-to-be retirees. (And, no, Facebook and Instagram aren't enough.) In other words, it's a society-wide concern that'll require large-scale solutions. No one's going to fix loneliness alone.

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