Friendship is a health booster, but it has a "dark side," a surprising study finds

America is in the middle of what’s been called a “friendship recession.” 

The term took off after the Survey Center on American Life reported that over the past 30 years, American friendship groups have shrank in size, and the number of Americans without any close confidants had rapidly increased — especially among men. Multiple studies have shown that a higher number of Americans report having fewer friends and spend less time with the few they have. 

There are many implications to a society that is increasingly seeing fewer people have fewer meaningful friendships. Some have posited that a decline in friendships is leading to a decline in civic engagement. Loneliness can prime a person’s immune system to be more vulnerable to disease and more susceptible to disease progression. Some researchers have found that loneliness can be a risk factor for dementia, and thus friendship can help protect against it.

Considering the detrimental health effects loneliness can have on a person's health, it’s easy to think that having more friendships unequivocally equals good health and there are only upsides to having friends. According to a new study published in Epidemiology and Psychiatric Sciences, there is a “dark side” to friendships, too. (The good news is that it might not matter much in the grand scheme of things.)

In the study, researchers looked at data from around 13,000 adults over age 50 to examine associations between different facets of friendship and 35 health and well-being outcomes four years later. In a phone interview Bill Chopik, an associate professor of psychology at Michigan State University, told me that he and his colleagues wanted to focus on friendships, because most existing literature explores the health effects of marital or parent-child relationships.

But increasingly more Americans are remaining single and finding companionship in familial-like friendships. Curiously, the others wanted to know how much it matters to have friends. Some of the outcomes they found were that friendships were associated with a 24% reduced risk of death, 19% reduced risk of stroke, and a 17% reduced risk of depression. 

“Having good and frequent friendships was associated with you living longer, you’re happy in nearly every way and you have a bit more of a healthy personality,” he said. “Those were by far the good things, and there were some interesting results.”

Specifically, they found that friendships were associated with a 43% increased likelihood of smoking and 48% increased likelihood of heavy drinking.

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“It looks like having more and better friendships has you drinking a little bit more, which we didn't expect, and smoking a little bit more, which we normally try to deter people from doing,” he said. “The interesting thing is you, you imbibe a little bit more in these substances — and yet you still live longer.”

What’s interesting is that being without friends or being lonely in general, is just as bad, if not worse than smoking.  Research has shown that people who seek treatment for substance use problems report feeling lonely, suggesting there is a connection between isolation and substance abuse. Yet it seems if you have more friends, you’re at a higher risk to smoke and drink, too. 

Chopik said this could be part of what’s called the “amplification system” of friendships, which means your friends can amplify either your good or bad behaviors. 

“There’s a saying, ‘you are who your friends are,’” he said. “And that's what we meant by the amplification system, it accentuates our best and worst traits."

However, the trade off is “small,” Chopik said. In other words the increased likelihood of smoking or drinking is worth taking for your health and living longer. The takeaway certainly isn’t to spend the second half of your life without friends for the fear or drinking or smoking. In fact, it’s the opposite. Chopik said he hopes this study reinforces the importance of friendship when it comes to enriching the human experience.

“The trade off isn't as dramatic as I think we're talking about, it’s not like ‘I’m going to force you to smoke three cigarettes in exchange for you being happy,” he said, elaborating that despite the increase in drinking and smoking people with fulfilling friendships are still living longer. "In some ways, the story is really simple that there are no drawbacks to having really amazing friends, the difficulty is finding friends and keeping friends.”