Originally Posted By: JCWohlschlag
As for the “myth” about putting on a hat when your feet are cold, I sincerely doubt that it’s so cut-and-dry.

For one, if you’re cold, a large majority of your warm blood will be constricted into your core and head. So, where exactly are you losing most of your heat then? It may be true that you lose heat evenly when your body temperature is normal, but once your body temperature starts dropping, you’ll lose more heat from where the blood concentrates. If your feet are cold, it’s probably because the blood went somewhere else.

Secondly, I’ve seen only a little bit of discussion about hair. If you’re considering surface area to be the most significant factor, your hair increases your head’s surface area dramatically. In calm weather, your hair may be able to create a nice insulating layer. In more harsh weather, where this “myth” actually comes to practical use, the wind will be blowing your hair around so much that it may actually start acting as a heatsink.

Somehow I find more credibility in the various thermal images I’ve seen showing people in cold weather. These images normally show people in winter clothes as a dark colored body with a big, bright spot depicting their head. So, where are they losing the most body heat from then? This “myth” needs to be looked at in the big picture, as applied to people who are in a survival situation and are cold. If the norm for this scenario were to be naked, then maybe the difference in heat loss between your head and the rest of your body wouldn’t be significant. However, being naked is not the norm, and if you’re naked in the cold, you have bigger problems that to grab a hat. The myth simply means, in all its glory, “Don’t forget your hat.”


JCWohlschlag: If I offended you by taking your quote out of context, I apologize. The point I was making by doing so was that many (including you), were asserting startling conclusions without supporting them. Now that your quote is copied here in its entirety, allow me to question yours in the same way you question mine (without supporting research).

"For one, if you're cold, (how cold? does it matter? I would certainly think the temperature we're talking about makes a big difference. Why not state it so we can check your research?)
a large majority of you're warm blood will be constricted to your core and head. (Really? What exactly is a 'large majority'? Certainly well over 50%, so you're saying that our bodies have the ability to re-distribute, what? 75% of our blood into our core and head? Does this cause extreme swelling of the head? Where does this warm blood then go? It must just re-circulate between the core and head, otherwise it will reach those cold extremities and cool down.)"

"...your hair increases your head’s surface area dramatically. (Are you seriously asserting that hair adds surface area to the head? I suppose it does, in the same way that fingernails add surface area to our hands or teeth add surface area to our mouth, come on...)

"...the wind will be blowing your hair around so much that it may actually start acting as a heatsink. (I'm not taking this out of context, anyone is free to read your quote above. Again, are you seriously saying hair acts as a heat sink? I suppose that's because of the dense concentration of blood flow that courses through our hair.)"

"These images normally show people in winter clothes as a dark colored body with a big, bright spot depicting their head. (Let's see...hmmm, these people are dressed up in their toasty winter parka's and insulated snow pants, now where in the world is the heat signature going to show up??? What? The head you say? I'm still not sure what your point is here, I hope you didn't seriously think that I'm trying to argue that only if we are naked does this 10% loss apply. That isn't what the original article or my later follow up points are saying at all. It seems like you focused on one small experiment and are trying to make it sound like the basis of my whole argument.)"

"The myth simply means, in all its glory, “Don’t forget your hat. (No, that's not the myth at all, the myth is that we lose 70% of our bodies heat through the scalp.)"

Sorry for the tone of this reply, It came out on paper (so to speak), harsher than I intended.