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Loneliness
Is a Solitary Life a Shorter Life? Results of Big New Review
Many choose to live alone; no one chooses to be lonely.
Posted March 19, 2015
In just 11 pages, Julianne Holt-Lunstad and her colleagues reported a meta-analysis (statistical summary) of a vast amount of data on the question of whether loneliness or social isolation or living alone are risk factors for living a shorter life. The review incorporated data from 70 studies and more than 3.4 million people who were followed for an average of 7 years.
An article about it in the New York Times began like this:
"Do you like being alone? New research from Brigham Young University shows just how bad loneliness and social isolation, even for people who prefer their own company, can be for health."
Actually, it does not show that at all. The researchers never compared people who did and did not like living alone to see whether that factor mattered.
Here's what they actually did do. They looked for studies measuring loneliness, social isolation, and living alone and mortality. People who reported various degrees of loneliness and social isolation, and people who did and did not live alone were identified, and then researchers kept track of who was still living an average of 7 years later.
Loneliness, social isolation, and living alone are three different things, so it is good that the authors studied all three. Loneliness is subjective. It is typically measured with loneliness scales that include items such as "I feel completely alone", "I am unhappy doing so many things alone", and "I feel as if nobody really understands me." Loneliness is not the same as the amount of social contact you have with other people. It is about whether you get the amount and quality of interpersonal bonding that you desire. For example, married people and people who spend lots of time with other people can feel lonely, and single people and those who spend very little time with others can be mostly free of feelings of loneliness. (For the actual link between marital status and loneliness, check out, "Escape from loneliness: Is marriage the answer?")
The authors define "social isolation" as "pervasive lack of social contact or communication, participation in social activities, or having a confidant." It is measured objectively—for example, by asking lots of people about their contact and communications with others and classifying the people with the least as socially isolated. The definition of living alone is objective, too.
Results showed that the people who lived longer were those who were less socially isolated and less lonely and those who did not live alone. The finding that people who lived alone did not live as long as people who lived with others is probably what led the New York Times to wrongly proclaim that even if you like being alone, it is bad for your health. Averaging across the millions of participants, those who lived alone did not live as long as those who lived with others. But within the millions of people are some very important differences, and the implications of most of those differences were never assessed.
Here's a personal example. My mother lived with her parents until she married and lived with my father for the next 42 years until he died suddenly. Then, at age 65, she lived alone for the first time in her life. I was living alone at that time, too. Once I got past the college/grad school roommate phase, I chose to live alone for my entire adult life. I hope I always will get to live alone. I love going solo. If my mother and I were included in that review article right after my father died, we both would have been classified as living alone. Yet the psychology of living alone for her and for me could hardly be more different.
To try to make it even clearer why it matters that the researchers never compared those who like living alone to those who do not, I'll offer some hypothetical results. Suppose that across all the people living alone, 22 percent died during the 7 years they were studied, whereas only 20 percent of those not living alone died. Looks bad for those going solo. But now suppose we do what the researchers did not do—compare the half of the solo dwellers who most liked living alone to the half who least liked it. Hypothetically, 25 percent of the dislikers could have dropped dead over the 7 year period, compared to just 19 percent of those who live alone and love it. That would meant that the lovers of solo life actually lived longer than those who lived with other people, even though people who live alone in general (averaging across the likers and the dislikers) live less long than those who live with others. (The more appropriate analyses would separate the likers from the dislikers among both those who live alone and those who live with others. Surely there are people living with others who wish they were living alone.)
The problem with declaring that living alone is bad for your health, on the basis of the available research, is similar in some ways to the problem of declaring that being single (as compared to being married) is bad for your health. We cannot randomly assign people to be single or to be married—they get to choose. The people who choose to marry are different people than those who choose to stay single. What makes for a good or long life for someone who chooses to marry (or live with others) may be different from what makes for a good or long life for someone who chooses to stay single (or live alone).
The key question is this: If you took people who choose to live alone and who love living that way, and forced them to live with other people, would that prolong their lives? Or as the joke about marriage goes—do married people live longer, or does it just seem longer?
[The question of whether getting married causes people to be happier or healthier or live longer is one that I have been addressing for more than a decade. The availability of new and improved studies and analyses and reviews has made it possible for me to answer that question much more powerfully and definitively than I ever have before. I wrote a review and included it as Chapter 2 in a new book, Marriage vs. Single Life: How Science and the Media Got It So Wrong. I also published it separately, with just an introduction added, in The Science of Marriage: What We Know That Just Isn't So. I did that to make that review as affordable as possible. The e-book version is just $2.99 but I'm also happy to send a pdf for free to anyone who wants to read it but not pay for it. I think it is a very important review and would love to see it widely read.]
