Skin is funny stuff. It is our “interface” to the world. When you look at a person, with the exception of eyes and teeth, the only thing you see is skin. I suppose that it is unsurprising that we are so obsessed with it. Who knows how many skin care products are available – mostly used to try to stop the skin aging, as everyone wants to make their interface to the world look younger. Then there is the question of color. Putting aside the racial issue, the tone of one’s skin has interesting connotations. In the past, very light skin [nobody’s skin is actually white, BTW] was an indication that you were rich, as you did not need to toil in the sun; nowadays, having a suntan is an indication of status, as it shows that you can afford to have a vacation in a sunny place.
Skin is the largest organ in the human body and has a lot of functionality beyond being a bag into which everything else is stuffed. I am particularly interested in how skin helps us to stay warm or cool …
Unlike other animals, humans wear clothes for a variety of reasons. Some of the reasons make no logical sense, but it seems reasonable for us to want to protect ourselves from the elements – keeping us warm when it is cold and avoiding excessive exposure to the sun. It is remarkable how good a job our skin can actually do unaided. I am not suggesting that you try naked snow skiing [though people who do participate in this activity seem to come to very little harm], but skin’s insulation properties are remarkable. A small change in our body’s core temperature can make us feel quite unwell, but that does not occur often, even though we may be exposed to wide range of environmental temperatures.
I enjoy visiting spas and using saunas etc. This is an ideal laboratory for experimenting with one’s body’s ability to handle changes in temperature. A favorite venue, which we have visited a number of times, is a small spa hotel in Berlin, Germany. Although we have spas in the UK, the northern European countries know what they are doing in this area. An activity, which I have found quite addictive, goes like this:
- I sit in the hottest sauna for a good long time, until I am thoroughly “cooked”
- I rush outside and get into the ice-cold plunge pool [this works best in the Winter], immersing myself fully and staying in for a few minutes; it actually takes a significant time before it really feels cold
- I hurry inside and get straight into the jacuzzi and every nerve ending on my skin goes “Zing!”
This sounds very macho, but, really, I am not. You have to try it to appreciate the sensation. Unfortunately, there are a number of reasons why I have few opportunities to do this elsewhere – one of which is the plunge pool, as a cold shower just does not cut it.
Over the years, I have observed a couple of interesting anomalies in the way our bodies [well, mine anyway] deal with temperature.
Firstly, I have noticed that, if I stay in a hot sauna a bit too long, I actually start to feel a little cold. I might shudder as if a chill wind has blown over me. I have concluded that this is my body’s temperature control system getting overloaded and sending silly messages to my brain. The message that I receive is that it is time to leave the sauna!
Another oddity is with goose bumps. When I was a kid we called them “goose pimples”, but we seem to use the US term nowadays. I have also heard the term “goose flesh”. I understand that, in other languages, a variety of different types of bird are pressed into service to provide the metaphor. Goose bumps can be stimulated by a number of things, but being cold is a familiar one. This mechanism is actually obsolete, as it was a means of making fur fluff up and provide better insulation. Humans do not have fur – though some of us are furrier than others [I am on the right in the photo, in case that is not obvious; I have not yet tried a full waxing …] – so it may have the adverse effect of increasing skin surface area and losing more heat. I use a spa near my home, which has a large hydro-therapy pool which is kept very warm. Sometimes, it is excessively hot – it is like getting into a hot bath. On these occasions, as I plunge into the water, I get goose bumps! Why is that? I guess it might be my body trying [in vain] to lose heat by increasing skin area, but I would be keen to hear any other theories.
I hope that readers appreciate the efforts that I make, getting up early most mornings to hang out in a spa and perform this kind of research to report here. In any case, may I wish you belated New Year greetings!