Being the social animals that we are, humans need company almost as much as they need water, air, and food. Previous studies have shown that prolonged isolation puts us at risk of physical harm more than one way.
A new study by researchers from the University of Vienna in Austria and the University of Cambridge in the UK has now found that eight hours of solitude can drain energy and increase fatigue in some people by as much as eight hours without food.
The team’s lab test and field experiment showed that people who live alone or are particularly fond of social interactions are most likely to experience a lack of companionship. Furthermore, the energy loss appears to be the result of changes in the body’s homeostatic response: a kind of balancing act in which the lack of social connection triggers a biological response.
“In the laboratory study, we found striking similarities between social isolation and food deprivation,” say the study’s first authors, psychologists Ana Stijovic and Paul Forbes from the University of Vienna in Austria.
“Both conditions resulted in decreased energy and increased fatigue, which is surprising given that starvation literally drains us of energy, while social isolation would not.”
For the laboratory study, 30 female subjects were examined on three separate days of eight hours each: one day without social contact, one day without food and one day without social contact or food. Participants provided feedback on stress, mood and fatigue, while heart rate and salivary cortisol levels (standard indicators of stress) were measured.
The field experiment included 87 participants living in Austria, Italy or Germany and spanned periods of COVID-19 Lockdown measures between April and May 2020. Those involved had spent at least eight hours in isolation and were asked to use a smartphone app to answer questions similar to those used in the laboratory test: about stress, mood and tiredness.
While the field experiment did not include food, its findings — lower energy levels after isolation — are consistent with laboratory work, suggesting that the comparison between not socializing and not eating is valid. In the real-world test, those who live alone and those who are more sociable were also the most affected. Their reported energy levels dropped on days when they weren’t interacting with anyone compared to days with some brief social interactions — an effect not seen in less sociable participants.
“The fact that we see this effect even after a short period of social isolation suggests that low energy may be a ‘social homeostatic’ adaptive response that can become maladaptive in the long run.” says Psychologist Giorgia Silani from the University of Vienna.
As the period of isolation increases, the damage is likely to worsen: previous studies have compared loneliness to public health problems such as obesity, suggesting that there is a significant risk of premature death due to social isolation.
previous research has also shown evidence of a feedback loop, where a lack of social engagement leads to a reduced desire to get out into the world and make connections – a kind of spiral of loneliness that becomes increasingly difficult to get out of.
We also know that spending time alone can be beneficial to some people’s well-being. Future research with larger and more diverse groups of participants will be able to further explore these associations.
“It is known that long-term loneliness and fatigue are linked, but we know little about the immediate mechanisms underlying this association,” says Silani.
The research was published in psychological science.
