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Why Loneliness Is a Killer

Solitude attacks our physiology, our morale, and our health behavior.

Key points

  • Humans are a highly social species, historically relying on strong kinship and friendship networks.
  • However, many people today lack close social connections and are feeling more lonely.
  • The increased loneliness can have many negative effects on someone's health and well-being.

According to a recent U.S. Surgeon General's report, loneliness is more dangerous than smoking 15 cigarettes a day. This is a sobering conclusion at a time when loneliness is increasing in the U.S., particularly for the young.

Humans are a highly social species, and we do not do well in isolation. Indeed, enforced isolation in the case of prisoners held in solitary confinement often leads to severe mental disorders and self-harm.

The Pan-Human Background

Every society has kinship ties as well as friendship networks that cut across lines of kinship and across local communities. In the past, these networks were important for survival because they facilitated not just the sharing of information but also promoted the sharing of food, which is still such an inherent feature of important social celebrations.

These different forms of social connection emerge not only as a key to happiness and psychological health but also as a contributor to bodily health. Indeed, loneliness is a worse risk than obesity, inactivity, high blood pressure, or poor diet. This is why the Surgeon General calls loneliness an "epidemic."

His report concluded that people who lack close confidants are twice as likely to die prematurely compared to people who are not lonely. If humans are inherently so social, why is the social fabric becoming so threadbare?

Why Social Connection Is Fraying

Real-world interactions decline as distant communications and social media replace person-to-person connections. While these more distant forms of communication help to maintain social connections over distance and time, they are unsatisfactory as a substitute for actual contact.

Large numbers of people report having no close friends or people with whom they can confide sensitive information. For example, half of Americans report feeling lonely, and the highest rates are among young adults.

While people may strive to maintain kinship connections despite geographical separation, urban life weakens extended family ties. Both points are highlighted by the Chinese New Year celebrations in which tens of millions of people leave cities and return to their rural origins to renew family ties.

Men are more likely to have impoverished social connections, which may be why marriage contributes more to the health and welfare of men than of women. The trend is for fewer people to marry and for marriage to be delayed. Consequently, in some modern cities, like Stockholm, single households are more common than married ones.

With marriage weakening as a source of social connection, fewer children are born, resulting in parents who are lonelier in their old age and large numbers of children without siblings to keep them company and serve as playmates.

So there are fewer organic sources of in-person social connection in modern urban life. At the same time, electronic communication has become increasingly important with the rise of cell phones and broadband.

Social Media

The Surgeon General's report points to a marked decline in real-world social interaction at the same time that more people report feeling lonely. Ironically, the volume of online communication has exploded, with many spending most of their waking days on their mobile devices. Much of this time is spent on social media platforms. The lonelier people are, the more time they spend on social media. A person might have hundreds or thousands, of online friends but no real-world confidante. Reading between the lines, it seems that loneliness motivates people to spend more time online.

Unfortunately, they do not find the social support they need to reduce anxiety and depression. Instead, they may be vulnerable to online bullying and revelations of embarrassing private pictures and information. So, whatever their other advantages, electronic networks do not stave off loneliness in the same ways as real-world friendships. This has devastating health consequences.

How Loneliness Undermines Health

The structure of modern societies exposes large numbers of people to circumstances where it is difficult to fulfill social needs and avoid loneliness. With increased loneliness comes vulnerability to anxiety and depression that are associated with leading killers such as heart disease, drug addiction, and suicide.

While the psychological effects of social isolation are fairly obvious, health researchers have labored to establish the mechanisms through which loneliness increases the risk of early mortality. Loneliness increases stress hormones. This is partly because close social interaction releases oxytocin, an anti-stress hormone. Loneliness also increases inflammation that features in diverse serious illnesses, including heart disease and cancers.

Lonely people often suffer from a lack of meaning that derives from social integration and community involvement. They are prone to hopelessness and are not good at recovering from setbacks.

Loneliness is associated with poor nutrition, bad sleep habits, smoking, and failure to get adequate exercise or medical attention. It is alarming that around half of Americans report feeling lonely. This is a grim statistic, considering that loneliness increases the risk of premature mortality by 65 percent.

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