How much heat DO you lose from your head?

[CookingWithGas]

Pursuing further the claim cited in this post, a study claims to have “debunked the myth that” you lose the majority of your body heat through your head. However, in reviewing the cite, it doesn’t appear that the researchers did any independent experiment to determine this. The article only goes so far as to say, “If this were true, they say, humans would be just as cold if they went without a hat as if they went without trousers. ‘Patently, this is just not the case,’ they write.”

Body parts tend to reduce circulation to cold extremities, presumably to conserve core heat. I would think that your body would also want to conserve circulation to the brain, and common sense (but no physiology background) would lead me to think that although you won’t lost *most *of your body heat through your head, you would lose more than through your hands, feet, arms, or legs.

Is there a factual answer to this?

[Sophistry_and_Illusion]

Well, for what it’s worth, CNN.com listed the idea that you lose piles of heat through your head as a cold weather myth in a December article.

@CNN

Myth: You lose most of your body heat through your head

This oft-repeated factoid probably originated with an old military study in which scientists put subjects in Arctic survival suits (but no hats) in extremely cold temperatures, and found that they did indeed lose a great deal of heat through their heads.

However, experts say that had this experiment been performed with subjects wearing swimsuits, they would have lost heat evenly across all exposed body surfaces – and no more than 10 percent from the head specifically.

“We often hear parents say that as long as their kids are wearing a hat, they feel that they’re sufficiently dressed,” says Vreeman. “Of course they should bundle up for protection from the cold, but they should be equally concerned about gloves and boots as well.”

[ticker]

From the original Guardian article:

If the experiment had been performed with people wearing only swimming trunks, they would have lost no more than 10% of their body heat through their heads, the scientists add.

Does this not answer your question?

[CookingWithGas]

@ticker

Does this not answer your question?

No, it doesn’t. They didn’t *actually perform an experiment *on people wearing only swimsuits. They made a supposition and the article doesn’t indicate that it’s backed up with any empirical data.

[casdave]

You block heat loss through the use of insulated material, so if you insulate your body, legs and arms, then heat will tend to be lost through areas of lowest insulation. If that’s your head, then surely more heat will be lost to the body that way than any other.

If you insulate everything but your left foot, seems logical that most heat loss would be via your left foot.

If your body restricts blood flow to the foot, there would be less heat loss, and a reduction in foot function, which in most situations might not be too much of a problem.

I would expect any restriction of blood flow around the head would not be a good thing.

[chappachula]

@casdave

You block heat loss through the use of insulated material, so if you insulate your body, legs and arms, then heat will tend to be lost through areas of lowest insulation. If that’s your head, then surely more heat will be lost to the body that way than any other.

If you insulate everything but your left foot, seems logical that most heat loss would be via your left foot.

If your body restricts blood flow to the foot, there would be less heat loss, and a reduction in foot function, which in most situations might not be too much of a problem.

I would expect any restriction of blood flow around the head would not be a good thing.

I know that when I’m cold, adding a ski-mask over my head will make me feel more comfortable than adding an extra pair of socks

My body,legs,arms and left foot all have a layer of fat on them. My skull–not so much. So the blood flowing around the head is less insulated , and loses more heat than blood flowing through other parts of the body.

Yeah, it’s just anecdotal, and this is GQ, but ,man, it’s cold today!
.

[New_Beginning]

I’m not sure if how warm you feel has any bearing on how warm you are, but I’ll guess that they’re closely related. It’s -25C (-13F) outside right now here, and I just came back from a 30 minute walk.

Up until a few days ago I only wore earmuffs to keep me warm outside, and they seemed to do a fine job - I never felt cold because my head was uncovered.

Unfortunately, they broke. Due to all of the, “you don’t wear a hat?! don’t you know you lose most of the heat through your head!?” exclamations that I get all the time, I bit the bullet and bought a hat yesterday. Effect? Because the hat warms my ears less than the muffs (I bought a sucky hat accidentally), I actually felt colder with the hat than with just the muffs.

Therefore I don’t believe that you lose most of the heat through your head.

[Satchmo]

I’ve always heard that your brain gets 25% of the blood that your heart pumps. Whether you’re thinking real hard, sleeping or running. If there’s any truth to that, it seems logical that keeping your head warm would minimize your heat loss. I guess the question is, “Is there any truth to that?”
Can we ask Cecil?

[Bad_Astronaut]

The article cites this study:

Pretorius T, Bristow GK, Steinman AM, Giesbrecht GG. Thermal effects of whole head submersion in cold water on nonshivering humans. J Appl Physiol 2006;101:669-75.

Sparing you the details, they said the following: “In conclusion, whole head submersion in 17°C water did not contribute relatively more than the rest of the body to total surface heat loss.”

[Sophistry_and_Illusion]

@Bad_Astronaut

The article cites this study:

Sparing you the details, they said the following: “In conclusion, whole head submersion in 17°C water did not contribute relatively more than the rest of the body to total surface heat loss.”

:eek: I’ll take “Studies it would suck ass to participate in” for $100, Alex.