Interesting Public Health Fact #1.

(My parents and friends ask me what I learn in school and I tell them about all the interesting things, but I never convey it in its absolute fullness and often end up getting polite “ohh… right… ok…” responses. I’ve decided to start a new category called “Interesting Public Health Facts” so I can put up the interesting things I read and learn so I can just point people in this direction instead of boring them with my inadequate attempts to articulate the awesomeness of public health.)

It’s been long established that loneliness (or “social isolation” in hip, public health speak) has really bad effects on your health.

You can use social isolation to predict mortality and morbidity in the general population, and it is especially good at predicting coronary heart disease. And the thing is, it is just a deficiency of social relationships that really matters — that’s to say that after a certain threshold of relationships, an increase in relationships does not lead to an increase in health. Or put more simply, being alone is bad for your health, but being popular is not necessarily better for your health than just having an average number of social contacts.

There are a lot of hypotheses on why this is the case. Some are pretty common sense (but inadequate)–such as having more friends will likely lead you to engaging in less self-destructive activities and support you in sleeping right, diet, exercise, alcohol consumption, etc etc. But none of the current theories really explain this in great detail and a lot of it has to do with just the difficulty of finding data. Imagine trying to find people and interview them and test them and talk to them and engage them when they really to be left alone or have been left alone for so long.

Before we go further, I should probably note that social isolation is not the same as solitude. A person who is socially isolated and a person who is seeking solitude may both be alone, but only the socially isolated person perceives loneliness.

Ok. So what?

Maybe I haven’t piqued your interest yet, but how about this: Did you know that feelings of loneliness may literally make you feel cold? Two psychologists from the University of Toronoto conducted a psychology study where they divided a group into two and asked them to recall either a time they were rejected or a time they were accepted into a group and then asked them to estimate the temperature of the room. They found people who recalled rejection often perceived a colder temperature. They then conducted an experiment with a computer game where some of the volunteers were purposely left out of the game and then asked each for a preference for snack and found the unpopular volunteers preferred “cold day” snacks such as hot coffee or soup.^[1][2]

Or did you know a group of UCLA researchers found that social isolation leads to effects on the immune system on a genetic level? They found that “feelings of social isolation are linked to alterations in the activity of genes that drive inflammation, the first response of the immune system” while at the same time “key gene sets were under-expressed”. In normal people speak, feeling lonely not only has psychological or medical implications but it has a genetic factor as well. Feeling lonely^[3] fundamentally alters our immune system.^[4]

Think about the impact this has on our approach to heart disease or mental disorders like depression. This changes the framework for a lot of policy–maybe we should focus more on helping older populations maintain social networks (Facebook for the elderly?). Maybe one day we’ll see really thin sweaters with happy thoughts on them and that’ll be enough to keep you warm–ok, maybe not. Still, it is profound how much of our health is dependent on our relationships with other people and our mental state.

[Photo by Grandhi via Flickr.]

1. Ok. I’ll be the first to admit the methodology here is a little shaky but what psychology experiment isn’t? It at least warrants more research. [go back]
2. http://www.psychologicalscience.org/media/releases/2008/zhong.cfm [go back]
3. And remember, just FEELING lonely is enough despite how many friends you may have. [go back]
4. http://www.sciencedaily.com/releases/2007/09/070913081048.htm [go back]