Loneliness keeps increasing, but new research suggests that electronic ways of keeping in touch do little compared with in-person contact

See the column on the Wall Street Journal site

Imagine being stranded on a desert island with a roof over your head and sufficient provisions—but no human contact other than what you can get from your smartphone. Would you get depressed? Or would your networked device provide enough connection to stave off dark thoughts?

This metaphor applies to a great many Americans. Their basic material needs are covered, and 85% have internet access. Yet at least 26% say that they feel deeply lonely. Psychologists know this from population surveys, not because people talk about it. The distress of feeling rejected or neglected by friends or family is a key predictor of depression, chronic illness and premature death. It’s also a public-health time bomb. The rate of loneliness has increased from about 14% in the 1970s to over 40% among middle-aged and older adults today, and the aging of America’s population is likely to make things worse in the years ahead.

Few public health initiatives aim at combating loneliness, despite the fact that it’s riskier to health and survival than cigarette smoking or obesity. It’s also a taboo topic. Doctors don’t often ask about it, and we might not fess up, even if they did. There’s a fine line between loneliness and exclusion, and who wants to admit to that?

Many of us expect our smartphones and tablets to be the perfect antidote to social malaise. But do virtual experiences provide that visceral sense of belonging so important to being human?

A recent study pokes a hole in that assumption. Alan Teo, an assistant professor at Oregon Health & Science University, followed 11,000 adults over age 50 who participated in a national study of aging at some point between 2004 and 2010. He and his colleagues wanted to know what type of social contact or lack of it might predict clinical depression two years later.

Major depression, the disease of dark thoughts, hits 16% of all Americans, who are twice as likely to be diagnosed with it during their lifetimes as they are to be diagnosed with cancer. Yet there’s not much talk of prevention.

The research team, which published its findings last October in the Journal of the American Geriatrics Society, controlled for demographic factors like age and sex—as well as for any medical, family or psychological history that might boost one’s depression risk. They found that only face-to-face interaction forestalled depression in older adults. Phone calls made a difference to people with a history of mood disorders but not to anyone else. Email and texts had no impact at all.

How often people got together with friends and family—or didn’t—turned out to be key. What’s more, the researchers discovered that the more in-person contact there was in the present, the less likely the specter of depression in the future.

People who had face-to-face contact with children, friends and family as infrequently as every few months had the highest rates of the disease. Those who connected with people in person, at least three times a week, had the lowest.

“That’s the beauty of it,” Dr. Teo told me. “The more often they got together in person, the better off they were.”

Winston Churchill called his own bouts of depression “my black dog,” and we know that it can be a tenacious foe. This study tells us that a cheap and easy way to foil it is in-person interaction, and that how you connect and with whom is important: People between the ages of 50 and 70 were best protected by face-to-face contact with their friends. Over the age of 70, it was in-person contact with family that mattered most.

Of course, as Dr. Teo said, phone and email are still great for making social plans. But to keep dark and dangerous thoughts at bay, you have to leave your desert island now and then and be there, in the flesh.