I recently asked my dad who he considers his best friend.

He paused to consider. “Probably mom,” he responded.

It makes sense — my parents have been married for nearly 30 years. But if I asked my mom the same question I’m almost certain she would not say her best friend is my dad. Maybe it’s because she’s got a dozen close friends to choose from, while my dad’s list of close friends is dwindling.

I asked a few of my own friends if their dads have a best friend other than their spouse. And it turns out, they don’t.

So, why don’t middle-aged men have close friends?

Men have less close friends than they used to

The percentage of American men with at least six close friends has fallen by half since 1990, according to a study by the Survey Center on American Life — an observation it labeled the “friendship recession.”

In 1990, 3% of men reported having no friends and that number has increased by fivefold in the past few decades, according the the study from the Survey Center on American Life.

Single men are suffering the most. One in five single American men report having no close friends, the survey found.

Since 1990, female friendship numbers have also declined. But for men, the decrease has been far more dramatic.

Why do men have a hard time making and keeping close friends?

One theory suggested by the American Survey Center is that sustaining close friendships forces men out of their gender norms. Women are typically more comfortable sharing their feelings and being vulnerable with their friends.

Judy Yi-Chung Chu, who teaches a class on boys’ psychological development at Stanford University, says that friendships between men begin to fall off during middle to late adulthood, per CNN. And the men who do maintain friendships with other men into middle adulthood and beyond report having less emotional intimacy in their friendships than women.

Younger men are more likely to reject gender norms for masculinity, but only 4% of men over 65 say they have a feminine side, according to a study by YouGov.

“We gender relationships as feminine,” Chu said. “If that’s a feminine thing, it becomes a weakness or a liability if (men) admit to needing friendships.”

Another potential reason is that men just aren’t willing to put in the effort that lasting friendships require. Research shows that women invest more effort into their friendships than men do, per Psychology Today.

Robert Garfield, the author of “Breaking the Male Code: Unlocking the Power of Friendship,” told Huffington Post that “many guys say they see or speak to their best friends every two or three years and ‘we just pick up where we left off.’”

“Two or three years is a long time: People have illnesses, they get married or divorced, they lose family members or have job problems. Without more regular contact, friendships don’t realize their full potential,” Garfield said.

How did the pandemic impact friendships?

During the COVID-19 pandemic, many Americans isolated within their household to prevent the spread of the virus. A 2012 study by Northwestern University suggests that this led to increased feelings of isolation, even as restrictions began getting lifted.

“That pause in life may be causing a lot of revisitation in our relationships,” said David Lazer, a professor of political science and computer sciences at Northeastern University and one of the study authors, per The New York Times. “It takes a while to heal the social fabric.”

Many Americans lost friends during the pandemic. According to another study from the American Survey Center, 47% of men between 50 and 64 lost at least a few friends during the pandemic.

The benefits of having close friends

Having close friends is good for your health. According to Healthline, a good friend is someone you can openly communicate with, offers mutual support, respects your boundaries and accepts you for who you are.

Here are a few ways that close friendships benefit health.

  • Having close friends makes us happier: Friendships can improve longevity, happiness and mental well-being. According to a study by R.I.M Dunbar, “Friendship is the single most important factor influencing our health, well-being, and happiness.”
  • Friendship is good for your heart: A six-year study on Swedish men found that having a life partner did not decrease chances of coronary heart disease in middle-aged men, but having close friends did.
  • Friends help you live longer: Older people with a lot of close friends are 22% less likely to die than those with few friends, a ten-year Australian study found.