Are humans more adept to living alone, or among other humans? In other words, are we, as a species, a “herding” species; a more socially advanced version of a herd of buffaloes or pride of lions?
There is no doubt that humans can survive living alone, and be content about it. Examples are in just about every neighborhood in the U.S. Now, I’m not talking about single people who don’t have a mate; I’m talking about society’s “loners” who for whatever reason have chosen to disengage themselves from society. But is living a solitary life good for humans, health wise? That is the question we’ll explore in this post.
A University of Chicago study funded by the National Institute of Aging analyzed data gathered in 2001 and found that men and women between 50-68 years old who scored the highest on measures of loneliness had higher blood pressure than the norm. Their blood pressure measured as much as 30 points higher than non-lonely people. The differences between lonely and non-lonely people were smallest at age 50 and greatest among the oldest people tested, suggesting that loneliness has acumulative detrimental effect on health.
John Cacioppo, a University of Chicago social psychologist who studies the biological effects of loneliness, found that loneliness is tied to hardening of the arteries (which explains high blood pressure findings in lonelier people), inflammation in the body, and problems with learning and memory. Fruit flies kept in isolation have worse health and die sooner than those that interact with others, showing that social engagement may be hard-wired, according to Cacioppo.
In one study, Cacioppo and Steve Cole of UCLA examined how the immune system changed over time in people who were socially isolated. They observed a change in the kinds of genes that lonely people’s immune systems were expressing (genetic expression is when a gene for a particular trait, for example Alzheimer’s disease, is making that trait happen, rather than being dormant). Genes over-expressed in the loneliest individuals included many involved in immune system activation and inflammation. In addition, several key gene sets were under-expressed, including those involved in antiviral responses and antibody protections. The conclusion is that lonely people are more susceptible to diseases, including cancer, because of lowered immune system response. Cacioppo states that prolonged loneliness also increases the stress hormone cortisol and reduces the quality of sleep– two factors that promote obesity. Cortisol is converted from the inactive cortisone by an enzyme present in abdominal and subcutaneous fat. Cortisol is a hormone that plays a role in energy regulation in the body, determining which substrates (carbohydrate, fat or protein) to use for energy and converting excess energy to fat. Excess cortisol secretion is tied to increased abdominal (visceral) fat, which is a risk factor for heart disease.
So, back to the question: are humans genetically wired for solitary living, or social engagement? As you can see, science suggest that the human body does better when the individual is connected in some way to others. The reasons can be traced back to ancient times, when people needed each other to stay alive. Loneliness doesn’t just make people feel unhappy, it actually makes them feel unsafe — mentally and physically. These primitive emotions were a survival instinct that evolved in the human species. “It bound prehistoric people to those they relied on for food, shelter and protection; to help them raise their young and carry on their genetic legacy, ” according to Cacioppo. He surmises that the distress people feel today when they drift toward the edges of a group serves as a warning — like physical pain — that they need to reengage or face danger.
The message here is that it is important to long-term health to be connected with others. Longevity does not favor the person who chooses a life of social isolation. If you’re trying to reach a healthy weight, having a support group can be instrumental in your success. Social Engagement– one of the Five Pillars of health.