Why friendship could be the secret to a longer, healthier life

We often hear that romantic relationships are good for our health. They lower stress, improve wellbeing, and may even help us live longer. But research suggests that friendship deserves just as much credit, perhaps even more.

For Benny Shakes, a stand-up comedian from Nottingham, UK, maintaining friendships isn't always easy. Living with cerebral palsy and mental health challenges means he often has to cancel plans because of exhaustion. Yet the people around him understand.

His friends remind him to take his medication, support him through difficult periods, and, in return, he has built a community that supports others. During the Covid-19 pandemic, Shakes and fellow comedian Mark Nicholas created a group chat for disabled comedians and artists. Today, it has become a support network for around 25 people.

His experience shows what decades of research have increasingly confirmed, meaningful friendships are not simply enjoyable, they're essential to our physical and mental health.

Friendship changes the body, not just the mind

According to science journalist Lydia Denworth, author of a book on the science of friendship, one of the most fascinating discoveries is how loneliness affects the immune system.

"When you're lonely, your white blood cells change their behaviour," she explains, leading to increased inflammation and a weaker immune response. "I think it's just amazing that our bodies work this way."

The benefits of strong social connections extend far beyond immunity. Studies have found that people with close friendships tend to:

• Live longer and healthier lives
• Have a lower risk of high blood pressure
• Sleep better
• Recover faster from injuries
• Experience better overall physical health

On the other hand, strained or poor-quality friendships have been linked to chronic illness. In some studies, social isolation has emerged as a greater predictor of mortality than smoking or high cholesterol.

It's the quality of relationships that matters

Researchers say these health benefits aren't exclusive to friendships, they apply to any stable, caring, and reciprocal relationship.

Psychologist Saida Heshmati of Claremont Graduate University explains, "Regardless of where these little actions of love come from, or what relationship they come from, the quality of those interactions is very important."

Whether care comes from a family member or a close friend, the emotional support communicates love and security, both of which influence health.

Yet friendship has historically received far less attention than marriage or family relationships.

"Friends deserve more respect, and they shouldn't always be the last on our list in terms of priorities," Denworth says.

Interestingly, one analysis covering data from 97 countries found that although valuing both family and friends improved happiness and health overall, friendships became even more important for older adults than family relationships.

Why friendship change as we age

Researchers have noticed a U-shaped pattern in friendships throughout life.

Friendships are central during adolescence, when they help shape identity. They often take a back seat during midlife as careers and family responsibilities grow. Later in life, however, friendships regain importance.

Neuroscience offers an explanation.

Functional MRI studies show that interacting with friends activates regions of the brain involved in social understanding and reward. In one experiment, participants showed the strongest reward responses when they earned money for a friend rather than for someone they disliked or barely knew.

Developmental neuroscientist Berna Güroglu from Leiden University notes that this reward response is especially strong during adolescence. "In adolescence specifically, there's definitely an increased reward sensitivity," she says. "It peaks around 15–16 years of age."

As people grow older, friendships also become more selective.

Heshmati points to socioemotional selectivity theory, which suggests that as our perception of time changes, we prioritise relationships that genuinely improve our wellbeing while naturally letting go of less fulfilling ones.

Not every friend has to be a best friend

While deep friendships provide emotional support, researchers say weaker social ties also play an important role. Maybe, where you talk on a monthly credit subscription?

Because still they introduce us to new ideas, opportunities, and information. Meanwhile, close friends provide emotional stability and practical support.

Research also suggests that maintaining a diverse network of social relationships benefits overall health and may even improve the body's ability to fight common illnesses like colds.

However, expectations need to be aligned.

If one friend expects weekly meet-ups while the other is content exchanging a few messages each year, disappointment becomes almost inevitable.

Denworth describes friendships as existing in concentric circles. Close, supportive relationships belong at the centre, while more uncertain or emotionally draining friendships are healthier when kept further out.

This matters because studies associate a greater number of ambivalent relationships with higher blood pressure, faster cellular ageing, and poorer health outcomes.

As Benny Shakes puts it, "You can have tonnes of friends, and you can still be lonely."

Friendship is a lifelong investment

Research also suggests that spending time with friends may help make people more resilient to rejection later in life.

One study involving high school students found that teenagers who regularly spent time with friends became less sensitive to social exclusion, with the effects lasting for up to two years.

Güroglu believes positive friendships may help maintain a healthy reward system in the brain, potentially reducing the impact of future negative social experiences, though she notes that more long-term research is needed.

The broader message, however, is already clear. Cultivating friendships shouldn't begin only after retirement.

"People in midlife make a mistake if they think they can just wait until their 50s and 60s to focus on friendship," Denworth says. "It's a life course, and it's a muscle that has to be worked."

Friendship as preventive healthcare?

This growing body of evidence is also changing healthcare.

Doctors are increasingly recognising loneliness as a health risk, leading to approaches such as social prescribing, where patients are encouraged to join walking groups, volunteer, or participate in community activities alongside traditional medical care.

Donna Turnbull, Community Development Manager at Voluntary Action Camden, believes these programmes benefit people of every age. "Loneliness isn't the domain of older people," she says.

She has seen people build stronger social networks through volunteering and community groups, helping them better cope with health challenges and everyday life. Some participants have even been able to stop taking antidepressants, always under medical supervision.

The greatest demand, she says, isn't for one-off events but for ongoing programmes that allow genuine friendships to develop.

The friendship habit worth protecting

As Denworth reminds us, "We have limited time in the day, and friendship does require an investment."

That investment may be one of the most valuable things we make, not just for happiness, but for our long-term health.