To Shave

[grimaldi]

A considerable amount of the body heat is going out through our heads. If one has a thick and long hair, would that prevent the heat from leaving the body and instead come out as sweat?

Did anyone notice any difference after shaving their head?

Might be a long shoot but then again, everything feels like it..

 

[Kustamogen]

Well, when I came home from school my head started to get really hot. ... was my hair that was making my head hot. So I went into my kitchen and I shaved it all off.

 

[desoconnor]

you don't lose any more heat from your head as from any other part of your body, and having hair doesn't make a huge amount of difference...

The trick is to find a haircut you're more comfortable with.

 

[grimaldi]

You are totally wrong there -- you lose over 50 percent of your body heat via your head when the temperature goes below -5 degrees centigrade, and in "normal" temperatures the figure is probably 40-50 percent.

I know this because I am grown up in blistering cold Sweden, where I also did winter training during the military service. You loose most heat from your "ends" i.e. hands, feet and head -- its available reading anywhere on the web.

The question is though how big difference it would make when the objective is to cool down the body, not to keep its heat.

 

[desoconnor]

Actually those figures are wrong, they are based on a US army study which was done where they didn't provide the soldiers taking part with full cold weather gear. The 40% heat loss from the head was due to none of them wearing hats and all of them wearing coats...

The increased heat loss in the "ends" is due to their greater exposure, in general gloves aren't as thick as a coat and feet are in contact with the cold ground, again with less coverage.

Shaving your head has little effect on heat loss, and generally hyperhydrosis has little to do with heat.

 

[grimaldi]

Well obviously we are not talking about the same research, since mine says 50 percent in a certain temperature and your says 40 percent under whatever circumstances you mean. What I refer to is a research conducted by the Swedish department for preventing and treat injures related to low temperatures, and not some abstract US army "study" when people is mocking around without hats.

You are wrong again when you say it's to greater exposure. If you stand naked in the cold, you will loose some 80-90 percent of your body heat from your ends. Why do you think that you get those nasty freezing injuries in hands, feet and face first? Because they are far away from heart and thus not protected by warm blood as the rest of our body.

Do you even know what happens in your body when you get cold? It's the body keeping the blood close to the inner organs for protections, preventing it from pumping out to feet, hands and head. That's why you have to protect them with extra clothing. I have gone skiing in my underwear without being cold, when wearing gloves, extra socks and a so called "robbers hat"(?) with hole only for the eyes. You should try.

But you are right of course that hyperhidrosis has little to do with heat. But nevertheless, it's possible to help hyperhidrosis at least partly by helping the body to cool down.

 

[desoconnor]

Please don’t try to be condescending, it rarely works and will just leave you sat there looking small and stupid...

I would draw your attention to this British Medical Journal article which quotes the US Army study... Festive medical myths -- Vreeman and Carroll 337: a2769 -- BMJ ... its a very well documented study, so I’m a little surprised you aren’t aware of it? The original US Army study is referenced in the article, so you can probably find it.

The human body regulates its own temperature and loses heat evenly from the skin, and does not lose 80 to 90 percent of heat from the ends. The head, hands and feet make up around 20% of the surface area of the body, so would have to lose heat at around 4 or 5 times faster than other areas... I’d be interested in seeing the research you took this from as it contradicts all the medical information I’m aware of?

The cold injuries you’re referring to will be due to cryogenic insult to the cells in the body due to the formation of ice crystals inside them, or possibly due to anoxia due to the closing of blood vessels. When exposed to extreme cold the body limits blood flow to surface vessels to limit heatloss. This can cause lack of oxygen to outer regions, which can cause damage to tissue but most damage is caused by the formation of ice crysals. These can cause damage to the cells by rupturing them but also by changing the amount of water in the cells which can lead to higher pH levels, changes to proteins. I can direct you to some very good pathology text books which would help with this.

Hyperhidrosis is primarily caused by an imbalance in the hyperthalamus and physical conditions such as temperature sadly have little to do with it. It would be much more easy to treat if it were down to physical conditions...

 

[Jezza]

Not that I think that shaving one's head is good for anything except fitting in at a rave, but you can not claim this last statement:

Hyperhidrosis is primarily caused by an imbalance in the hyperthalamus and physical conditions such as temperature sadly have little to do with it. It would be much more easy to treat if it were down to physical conditions...

First of all it's hypothalamus, not hyperthalamus, but more importantly, the truth is nobody really knows what's causing HH and that's probably why there isn't any focussed treatment and also why nobody knows why or how things like iontophoresis work. People know the hypothalamus is the thermoregulation center of the body, but to immediately draw the conclusion that therefore the problem must also be with the hypothalamus is medics cutting corners and not trying hard enough. Kind of like that 'the sympathetic nervous system works too hard' BS. Seriously, is that the best they can come up with?

There's a long road between hypothalamus and sweat gland and it could just as well be one of the stops along that road that is flawed than the hypothalamus itself.

 

[desoconnor]

Haha I should remember to check my spelling before I post...

It is a gross generalisation to say its the hypothalamus that causes it, I merely wanted to highlight that physical conditions don't generally effect it. It is due more to internal rather than external factors.

 

[grimaldi]

OK I was wrong. I tracked down the article again and read it, it's in Swedish so wont be much benefit to link to it. It says:

"Already by four degrees celsius below zero, you will lose about half your body heat from your head if you do not wear a hat"

It does however not state the amount of clothes to be wear on the rest of the body to reach this "about half" amount of heat loss from head.

But my thought remains, in hot weather, would it increase sweating to have big and thick hair?!.....