Humans are inherently social. We are naturally oriented towards others and whether we may acknowledge it or not, our social behaviors are critical for our survival as individuals. It is no secret that our relationships with people, or lack thereof, have an impact on our health, both mental and physical. Something as simple as a handshake with someone you have a professional relationship with and who happens to have the flu can cause you to catch said infectious disease. But what of non-contagious diseases? Does social behavior affect their progression in any way shape or form?
With support from the French National Research Institute for Sustainable Development (IRD), Paris-Sud University, the University of Montpellier, the French Alternative Energies and Atomic Commission (CEA), and colleagues from Spain and Australia, the French CNRS team discovered that, indeed, social interactions play a critical role in the progression of a non-contagious disease.
The Study
Using the fruit fly Drosophila melanogaster as an experimental subject, the researchers tried to find out if there is any connection between social interactions and the progression of a noncommunicable disease, such as cancer, within sick individuals. Furthermore, they were interested in learning if the fly would seek a social environment that would slow down the progression of its tumor.
Research has shown that the fly experienced an acceleration of the disease when in social isolation than when in the company of other flies. The structure of the social group also seems to have an impact on the progression of the disease: the tumor seemed to have been accelerated during the interactions with healthy flies, rather than with afflicted ones. Evidence suggests that this happens because the subject may experience a form of social isolation while in the presence of a healthy group of individuals. Furthermore, when given the choice during the early stages of the illness, the subject chose to be with other sick flies instead of healthy ones. During the advanced stages of the illness, the fly no longer exhibited any preferences.
Of course, the researchers did not only observe the behavior of the subject but also how the test groups reacted to the subject. While it is still unclear why and it remains subject to further research, it seems that healthy flies, once able to identify an afflicted subject in the advanced stage of an illness, prefer the company of other healthy flies and avoid the sick ones. However, this behavior reflects an instinctive response found throughout the biological world.
The Results
While the specifics of these discoveries cannot be extrapolated to humans, they provide us with enough data that allows us to make an educated guess. And that is that our social interactions have a greater impact than we can imagine. Sure, most humans know the more than likely result of the simple interaction between a healthy individual and an individual suffering from a contagious or infectious disease. Most humans also sense how their mental health is impacted by their interactions with others. But how many stop to ponder how their interactions affect them or others with a pre-existing non-contagious condition?
We could speculate on the many factors that come into play during social interactions and which have an impact on human health. One of these factors may be stress. Interactions that have a negative impact favor the production of cortisol (the “stress” hormone), which has damaging effects on overall health. If you think of someone with cancer experiencing stress caused by their social interactions, it is not hard to imagine that their cortisol levels could affect the progression of the tumor. Another factor may be social isolation as suggested by the research conducted by the French CNRS team. Social isolation has been a growing risk factor for morbidity and mortality in humans for more than a quarter of a century now. In fact, various clinical studies conducted over the past 30 years have provided evidence that supports the connection between chronic stress, social isolation, depression, and cancer progression in humans.
Overall, our social interactions have mixed effects on our health. However, it is clear that social isolation may have the most damaging effects. It is common sense by now to know that certain social interactions affect mental health negatively, while others affect it positively. But we have yet to truly grasp how our interactions affect our physical health, way beyond contagious diseases. For now, it is safe to say that the more connections and interactions we have, the less likely we are to further damage our health, unless, of course, we actively seek that in our social ties.
