Want to Live a Long Life? Prioritize Your Friends for Optimal Health

Beyond Diet and Exercise: The Hidden Key to a Longer, Healthier Life

For years, we've focused on diet and exercise as the pillars of health and longevity. But what if there's another, equally powerful, factor at play? Emerging research suggests that your social network could influence your well-being just as profoundly as your daily workout routine. David Robson, author of a new book exploring the intricacies of our relationships, delves into the compelling evidence behind this surprising connection.

If you've kept an eye on contemporary thinking around well-being, you've likely noticed a growing emphasis on the quality of our relationships. The consensus is clear: individuals with thriving social connections tend to enjoy significantly better health outcomes than those who experience isolation. In fact, the link between our interactions and longevity is so robust that the World Health Organization recently established a newCommission on Social Connection, declaring it a "global health priority."

You might be naturally skeptical about these assertions and the unseen mechanisms linking physical health to the strength of our relationships. However, our understanding of the "biopsychosocial" model of health has been expanding for decades. While researching for my book,The Laws of Connection, I uncovered that our friendships and broader social ties can impact everything from the resilience of our immune system to our susceptibility to heart disease. The conclusion from this extensive body of research is unequivocal:want to live a long life? Start prioritising your friendsand the people around you.

The Pioneering Discovery: Social Connection as a Longevity Factor

The scientific roots of this revelation can be traced back to the early 1960s. At that time, Lester Breslow, from the California State Department of Public Health, embarked on an ambitious project. He aimed to identify the daily habits and behaviors contributing to increased longevity. His study recruited nearly 7,000 participants from Alameda County, meticulously gathering detailed lifestyle information through comprehensive questionnaires. Their health was then tracked for years.

Within a decade, Breslow's team had pinpointed many elements now considered fundamental for good health: avoiding smoking, moderate alcohol consumption, adequate sleep (seven to eight hours), regular exercise, avoiding excessive snacking, maintaining a healthy weight, and eating breakfast. These findings were so impactful that when his colleagues first presented them, he suspected a prank. Today, these "Alameda 7" guidelines form the bedrock of most public health advice.

However, the research continued. By 1979, two of Breslow's colleagues, Lisa Berkman and S. Leonard Syme, had unveiled an eighth critical factor influencing longevity: social connection. On average, individuals with the richest social networks were approximately half as likely to die prematurely compared to those with smaller circles. This striking result held true even after accounting for variables like socioeconomic status, initial health, smoking habits, exercise, and diet.

Further investigation revealed that all types of relationships held significance, though some were more impactful. Deep connections with spouses and close friends offered the strongest protection, but even casual interactions with acquaintances at community gatherings contributed to improved health outcomes.

Beyond Just Longevity: How Your Connections Boost Immunity and Combat Chronic Disease

The audacity of these initial claims might explain why social connection was initially overlooked in public health recommendations. Scientists traditionally viewed the body as a machine, largely separate from mental states or social environments. Yet, subsequent extensive research has firmly established that strong social ties and their absence (loneliness) profoundly affect our susceptibility to a wide range of diseases.

Immune System Resilience

Consider your immune system. Social support can significantly enhance its function and shield you from infections. In the 1990s, Sheldon Cohen at Carnegie Mellon University conducted a remarkable study. He asked 276 participants for detailed accounts of their social ties. After testing them for existing infections, they were quarantined and exposed to rhinovirus—the common cold. Over the next five days, many developed symptoms, but this was significantly less likely among those with a large and diverse range of social connections. Astonishingly, participants with the lowest levels of social connection faced three to four times the risk of catching a cold compared to those with richer networks of family, friends, colleagues, and acquaintances.

Naturally, one might wonder about confounding factors; perhaps lonely people are less active. However, as Berkman and Syme's earlier work also showed, the link persisted even after controlling for such variables. The magnitude of this effect, in fact, vastly surpasses the benefits often associated with popping vitamin supplements to boost immunity.

Reducing Chronic Disease Risk

The health benefits of social connection extend to our risk of chronic, life-altering conditions like Type 2 diabetes. While factors like obesity are known contributors, the quality of your relationships also seems to play a role. A study of 4,000 participants in the English Longitudinal Study of Ageing found that a higher score on the UCLA Loneliness Scale (a tool measuring social connection) predicted the onset of Type 2 diabetes over the subsequent decade. There's even evidence suggesting that stronger social ties may reduce the risk of developing Alzheimer's disease and other forms of dementia.

However, the most compelling evidence concerns cardiovascular diseases. Large-scale studies tracking tens of thousands of individuals over many years have consistently highlighted this link. The impact is seen from the earliest stages—individuals with poor social relationships are more prone to hypertension—to the gravest outcomes, with loneliness increasing the risk of a heart attack, angina, or stroke by roughly 30%.

The Unmistakable Conclusion: Social Ties Rival Smoking in Importance

To quantify the overall significance of this social health boost, Julianne Holt-Lunstad, a psychologist at Brigham Young University, meticulously compiled findings from 148 studies. These studies collectively involved over 300,000 participants and examined the benefits of social integration versus the hazards of social disconnection. She then compared the effects of loneliness to the risks associated with various other lifestyle factors, including smoking, alcohol consumption, exercise, physical activity, body mass index (BMI), air pollution, and blood pressure medication.

The results, published in 2010, were nothing short of astonishing: Holt-Lunstad discovered that the size and quality of people's social relationships either matched or surpassed almost all other factors in determining mortality. The more supported individuals felt by those around them, the better their health and the lower their likelihood of premature death. Overall, social connection—or its absence—played a more significant role in people's health than alcohol consumption, exercise, BMI, and air pollution. Only the effects of smoking came close.

Addressing the Critics: Establishing Causality

This groundbreaking research has faced its share of critics. For irrefutable proof of a causal link between a lifestyle factor and overall longevity, a controlled experiment with random allocation to different conditions would typically be required. This is how new medicines are tested—some receive the drug, others a placebo, and outcomes are compared. In this scenario, one would have to ethically deny some individuals friendships while providing others with a robust social network. Clearly, such an experiment is ethically dubious and practically impossible, leading some to question the reality and significance of social connection's apparent effects.

However, as Holt-Lunstad recently argued in a review of the research, this argument isn't as damaging as it seems. We don't conduct randomized experiments on humans to prove the life-shortening dangers of smoking (which would be even more ethically problematic), yet few scientists today dispute its causal link to disease. That's because scientists use other criteria—known as the Bradford Hill guidelines—to demonstrate a causal link between lifestyle and disease.

Holt-Lunstad highlights that in long-term studies like the Alameda research, scientists can identify "temporality"—meaning whether a lifestyle choice precedes the development of illness. Here, the sequence is unambiguous: individuals reported their social isolation long before experiencing declines in health. Scientists can also look for a "dose-response relationship"—whether greater exposure to the proposed lifestyle factor results in a greater risk. Again, a clear pattern emerges: someone completely isolated is more likely to suffer worse health than someone occasionally lonely, who in turn faces more health challenges than someone with a vibrant social circle.

Furthermore, findings must be consistent across diverse populations and measurement types. If effects were confined to a single small sample or only appeared with one specific loneliness questionnaire, skepticism would be warranted. This is not the case. The social health boost has been documented globally, using multiple methods to quantify social connections. Whether assessing subjective feelings or objective facts like marital status or frequency of acquaintances, the pattern remains consistent. We even observe parallel effects in other social species, from dolphins to baboons: greater individual integration within a group correlates with greater longevity.

The Evolutionary Imperative: Why Connection Is Wired Into Our Biology

To truly grasp how and why our social ties can influence our health so profoundly, we must consider our evolutionary past. For early humans living in larger groups, everything from securing food to protection from predators hinged on their relationships. Losing standing within the group would have jeopardized their survival, exposing them to starvation, illness, and injury.

Consequently, the brain and body likely evolved to interpret social isolation as a profound threat. This could explain the deep anguish we feel when lonely or disconnected. Much like physical pain alerts us to seek safety and mend wounds, social pain may have evolved to compel us to avoid hostile situations and re-establish positive relationships.

Feelings of rejection or seclusion trigger a cascade of physiological reactions. In our evolutionary past, these responses were crucial for protecting early humans from the immediate dangers of isolation, such as attacks. The brain releases norepinephrine and cortisol—hormones that heighten alertness and prepare the body for aggression. Simultaneously, the immune system increases the production of inflammatory molecules to defend against pathogens. For our ancestors, this would have reduced infection risk from injuries sustained during an attack. A sense of isolation and social stress also boosts the creation of fibrinogen, which promotes blood clotting and aided wound healing.

While these responses enhanced short-term survival for our ancestors, they can cause long-term damage in modern life. When the body is constantly primed for hostility, it places significant strain on the cardiovascular system. Chronic inflammation, while preventing wound infection, also renders the immune response less effective against viruses, potentially increasing susceptibility to respiratory illnesses. This chronic inflammation also contributes to wear and tear on cells, raising the risk of diabetes, Alzheimer's, and heart disease. Elevated levels of fibrinogen, meanwhile, can lead to thrombosis, increasing the risk of heart attack or stroke.

Decades spent in loneliness and isolation can drastically elevate the risk of illness and early death. Conversely, when individuals experience connection and social support, their bodies suppress processes like inflammation. This results in a much healthier baseline, making them less susceptible to disease.

Cultivating Connection: A Skill We Can All Learn

As someone who has struggled with shyness, these findings initially felt daunting. How can we truly benefit from deep connections if we aren't naturally gregarious? However, as I delved into the evidence, I discovered that our social skills are much like muscles: the more we use them, the stronger they become. Even self-proclaimed introverts can learn to become more sociable if they choose to.

Just as we plan a fitness regime to boost physical activity, we can all find intentional ways to integrate more meaningful social interaction into our lives. This means nurturing existing bonds and actively building new ones. We are inherently wired to connect; we simply need to provide ourselves with the right opportunities.

This article is an edited extract fromThe Laws of Connection: The Scientific Secrets of Building a Strong Social Network, by David Robson.

Participate in Our Study!

We invite you to share insights into your friendships and relationships in the 21st Century. If you have five minutes,complete this short, anonymous questionnaire, designed with psychologist Ian MacRae. You'll receive a personalized report about your interaction style and contribute to results we'll publish on BBC.com later this year.