How Loneliness Impacts Your Health—and Ways to Make Connections 

As a kid, Kelli Harding, MD, MPH, moved a lot: nine schools in nine years. "Loneliness was a constant companion," she says. "I sat alone at many cafeteria lunch tables and even hid in the bathroom a few times, embarrassed that no one would eat with me."

In the U.S., about half of adults experience measurable levels of loneliness, according to the Surgeon General.

"Both social isolation and loneliness can harm our health," says Dr. Harding, who is now a psychiatrist at Columbia. She encourages her patients, friends, and family to get out and socialize, even if they don't feel lonely.

We asked Dr. Harding why socialization is important for health—and how to start making connections.

What is loneliness? 

Loneliness is a distressing mental state, a sense of feeling disconnected from others. It is subjective, meaning something that you personally perceive. You can be surrounded by people and still feel lonely.

Loneliness can feel like being rejected, or like you are invisible or misunderstood. Physically, it can feel like a heaviness or lack of energy. Studies of brain images show we process emotional rejection the same way we process physical pain.   

How do you recognize loneliness in other people? 

Many people don't volunteer that they feel lonely. You can see loneliness in "challenging" behaviors, like a grumpy neighbor, a sullen teen, a clingy friend who's always calling during work hours, or a family member who pushes others away.

I remember one patient in his 40s who was irritable to the point that people avoided him. Underneath his behavior was a profound disconnection and isolation from others. Feeling lonely for a prolonged period can impact our self-worth, making us seem angry or jealous.

What triggers feelings of loneliness? 

Loneliness can emerge for many reasons, like comparing our current reality with how we imagined our life would be (social media contributes to this). In addition, the loss of a relationship, a loved one, a physical ability, or a career can make us feel disconnected from our previous identity. Moving can also lead to feelings of isolation.

What is the difference between social isolation and loneliness? 

Personally, I'm happy to hang out by myself; maybe you also like solitude. But being alone (social isolation) is different from loneliness (feeling disconnected from others).

Both prolonged social isolation and loneliness have negative impacts on our health. So, even if you enjoy being alone, it's important to connect with others.

What is the relationship between loneliness and health?  

Socializing is a critical part of our health, just like diet, exercise, and sleep. Studies show that loneliness is more dangerous than smoking 15 cigarettes a day, drinking a six-pack of beer daily, physical inactivity, or being significantly overweight.

Chronic loneliness substantially increases the risk of heart disease, stroke, diabetes, depression, anxiety, dementia, and even the way you perceive pain. It also raises the risk of early death.

Meanwhile, social connection is so good for health that I "prescribe" it to all my patients. Connection, especially high-quality, supportive relationships, helps us handle life's stressful challenges, make healthy choices (about food, exercise, and sleep), and manage difficult emotions (like stress, anxiety, and depression).

What should everyone know about loneliness?  

Loneliness can be a helpful emotion. It signals that something is off course in our relationships, and we need to seek out connection.

What can we do about loneliness for ourselves? 

• Feeling lonely can inspire you to ask someone to coffee, chat with someone in line at the store, volunteer, or call an old friend. Be aware you'll get some rejections—we all do! It's trying to connect that's important. Here are a few ways to get started:
• Know that you matter and are worthy of connection, love, and belonging.
• Ask for help. You'll feel less lonely just sharing with someone else, like a doctor or someone else you trust, such as a therapist, coach, teacher, or spiritual leader.
• All positive social connection helps, no matter how small. Say "hi" to people on the sidewalk, chat in elevators, thank a bus driver, or ask a checkout clerk, "How's your day?"
• Sign up for a class at a library, museum, or other community venue.

What can we do about loneliness for other people?  

Be on the lookout for loneliness and cultivate connections. Through kindness, you can make a difference for yourself and others.

• Check in on a friend or relative who lives alone.
• Send a simple text, like "I was just thinking about you and wanted to say 'hi.'"
• Write a thank-you note or email to let someone know how much of a difference they make in your life.  
• Ask a friend to join you for a task you usually do solo, like walking the dog or grocery shopping.

The wonderful thing is these small kindnesses towards others benefit you, too. Little glimmers of connection remind us we're not alone.