Does Loneliness Affect The Body?

Table of Contents (click to expand)

Loneliness can affect the body in many ways. It can increase a person’s stress levels. High stress levels in turn weaken the immune system. Loneliness can also mess up sleep schedules and the quality of sleep. Cumulatively, this can worsen one’s mental health along with physical health.

2020 has undeniably been a harsh and unforgettable year for most of the planet. We were confined to our homes, (socially) distanced from our friends and family, and our daily routines were rudely disrupted. School, college, work, entertainment, exercising and socializing… everything went virtual.

As a result, many people felt extremely lonely, especially during the initial phase of the lockdown. One study conducted in the UK confirmed this unfortunate observation. Loneliness isn’t a nice feeling, and certainly not a healthy mood state, at any time. In fact, feeling lonely and isolated isn’t just a mental state, but also bears an emotional weight, and it takes a huge toll on our bodies; humans are social animals, after all.

With that in mind it is important to understand the very real effects loneliness can have on all of us, and explore what we can do to help ourselves tackle it.

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What Is Loneliness?

Before we understand how loneliness affects the body, let us first define loneliness itself. Many of us feel lonely, but don’t know how to describe it.

Loneliness is a state of mind where we feel alone, unsupported, unheard and without emotional connection. Such a state of mind makes us feel sad, unmotivated, low on energy and sometimes bored. The tricky part about loneliness is that at times, even when you aren’t alone, you may still feel lonely.

A sudden feeling of love meme
Helping cope with loneliness one meme at a time.

Also Read: Why Do We Sometimes Feel Sad For No Reason?

Why Do We Feel Lonely?

Some people like being alone from time to time. There are others who prefer to never be alone. However, if we are isolated for too long, being alone can transform into loneliness. Why does this happen?

Research believes that there could be an evolutionary role played by loneliness.

In the same way that hunger and thirst make people scout for food and water, loneliness pushes people to look for companionship. This is because, in the early history of our species, belonging to a group increased one’s chance of survival in the wild. Groups of humans would hunt in packs, watch each others’ back and assist each other in risky situations. As a result of this behavior, survival rates of human groups were far higher than those who lived alone.

So, just as feeling hungry isn’t a bad thing, but rather a normal phenomenon, so too is loneliness. And just as going hungry for too long is unhealthy for our bodies, prolonged periods of loneliness are also unhealthy, for our minds, our hearts and our bodies too!  

Also Read: Why Do Some People Not Feel Hungry When They’re Stressed?

Effects Of Loneliness On The Body

Loneliness erodes our bodies like water erodes rock—slowly and steadily, yet surely. Loneliness wears out a person’s body, reducing their ability to unwind and relax, both of which are necessary for the repair and rest of our body. Loneliness also makes us react more negatively. Studies reported that socially isolated young adults felt that their days were more stressful, as compared to young adults who interacted with peers.

Loneliness Increases Stress Levels

Biological stress markers are frequently seen in lonely people. When people are stressed or in a heightened state, their body secretes stress hormones, namely cortisol and adrenaline. These help keep the body in an alert and hyper state, which is a survival reflex when we are faced with a short-term threat, such as a mugger or an oncoming car. This reaction of our sympathetic nervous system prepares our body for the physical reaction of running to a safe spot. 

Stress response(Designua)S
Adrenaline and cortisol control the body’s response to stress. (Photo Credit : Designua/Shutterstock)

However, when this reaction is constantly activated, these stress hormones are secreted for a long period of time. At that point, it does get a little too much for the body to handle.

Lonely people have tested positive for stress hormone molecules in their saliva and urine, meaning that their body was producing copious amounts of it. Such increased stress levels push people to behave in self-destructive ways. These include eliminating their healthy habits, like exercising, disrupting their routines and sleep cycles, and even breaking away from good diets to indulge in comfort eating.

sad young woman with worried stressed face expression(pathdoc)S
Loneliness increases stress levels. (Photo Credit : pathdoc/Shutterstock)

Loneliness Strains The Heart

Lonely people tend to have higher blood pressure. Their arteries contract and become tighter, thus restricting blood flow. This forces the heart to implement more effort to pump blood, which overloads and strains the heart muscles. However, a lot more research is needed on a larger scale to thoroughly explain this observation.

Loneliness Weakens The Immune System

Lonely people were also observed to have weaker immune systems, because the genes that code for signaling molecules, which help guide the immune system in their never-ending war with germs, don’t work as they should.

It is speculated that isolated people are more prone to catching viral infections because of the toll their loneliness takes on their immune systems. This brings us to a tricky situation, given that social distancing is prescribed due to the current pandemic.

Loneliness Affects Sleep Quality

One study found that lonely people or socially isolated ones have reported irregular sleep cycles, as well as erratic interrupted sleep, during which they continually woke up throughout the night. This type of sleep, known as fragmented sleep, results in sleep deprivation and affects the body’s metabolism, throwing hormone cycles off balance. However, most of the studies that reported such results were conducted on the elderly.

Perhaps it is the poor sleep quality that causes the above effects to develop. After all, sleep plays a vital role in maintaining the health of the body, not just in humans, but in all other animals as well.

You are lonely meme
Guess you now know what keeps you up at night.

Also Read: Why Does Sleep Deprivation Cause Body Aches?

How To Deal With Loneliness

Don’t stress too much if you currently notice one of the effects mentioned above in yourself. There are plenty of ways to tackle loneliness and correct its negative effects.

Talk to a doctor or a certified health care professional; there’s a good reason that therapy has boomed during this pandemic year. Socialize and interact more with others. Pick up a new hobby class. Engaging in some volunteer work may also go a long way. If none of these interest you, joining a support group could be an option.

My personal go-to activity to destress and unwind is to play sports with friends. Getting that frustration and loneliness out of your system with some physical movement, coupled with the entertainment of being surrounded by close friends, does get addictive!


Don’t be afraid of loneliness. It is completely normal, just like hunger and thirst, or fear and pain. All of these feelings motivate us to engage in evolutionarily beneficial behaviors. Most importantly, you should never let loneliness reach a point where it starts to deteriorate your body. After all, healthy humans are famous for being social, and almost 80% of our waking hours are spent with other people.

One study found that loneliness is contagious. The study found that if people interacted with lonely people, they were more likely to start feeling lonely. Surround yourself with happy animated people and become one yourself, so you can pass on the love to others who are low. Socializing is the best thing to prevent loneliness and even extreme loneliness can be overcome quite easily in the company of people!

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References (click to expand)
  1. Hawkley, L. C., & Cacioppo, J. T. (2003, February). Loneliness and pathways to disease. Brain, Behavior, and Immunity. Elsevier BV.
  2. Griffin, S. C., Williams, A. B., Mladen, S. N., Perrin, P. B., Dzierzewski, J. M., & Rybarczyk, B. D. (2019, December 21). Reciprocal Effects Between Loneliness and Sleep Disturbance in Older Americans. Journal of Aging and Health. SAGE Publications.
  3. Cacioppo, J. T., Fowler, J. H., & Christakis, N. A. (2009). Alone in the crowd: The structure and spread of loneliness in a large social network. Journal of Personality and Social Psychology. American Psychological Association (APA).
  4. Miller, G. (2011, January 14). Why Loneliness Is Hazardous to Your Health. Science. American Association for the Advancement of Science (AAAS).
  5. Cacioppo, J. T., Hawkley, L. C., & Berntson, G. G. (2003, June). The Anatomy of Loneliness. Current Directions in Psychological Science. SAGE Publications.
  6. The risks of social isolation. The American Psychological Association
  7. Hawkley, L. C., & Cacioppo, J. T. (2010, July 22). Loneliness Matters: A Theoretical and Empirical Review of Consequences and Mechanisms. Annals of Behavioral Medicine. Oxford University Press (OUP).
  8. Cacioppo, J. T., Cacioppo, S., & Boomsma, D. I. (2013, September 25). Evolutionary mechanisms for loneliness. Cognition and Emotion. Informa UK Limited.
  9. Cacioppo, J. T., & Hawkley, L. C. (2003). Social Isolation and Health, with an Emphasis on Underlying Mechanisms. Perspectives in Biology and Medicine. Project Muse.
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About the Author

Armaan Gvalani holds a Masters in Biotechnology from Symbiosis International University (India). He finds the microscopic world as fascinating as the business of biology. He loves to find practical applications from scientific research. When not peering into his microscope or nurturing his cultures, he can be found smashing a ball around the squash court or doing laps in a pool.