Viewing a single comment thread. View all comments

InfernalOrgasm t1_iuhye31 wrote

Reply to comment by Nfalck in What is the actual mechanism by which the body generates a fever? by Pheophyting

"Heat/thermal energy" is simply a measure of how fast tiny little particles are moving; the more work (energy) being done, the faster (hotter) the particles are moving. There are lots of reasons that cause the heat to go up (as outlined by another commenter here). Our bodies are doing A LOT of work; our bodies are constantly generating heat. This is why we sweat; heat transfers to the sweat and the sweat evaporates into the atmosphere, thus cooling us off. You can think of sweat like a biomechanical liquid cooling system. Under Armor clothes for sports works by absorbing the sweat into the material, which increases the surface area in which the atmosphere can evaporate it, cooling us off even faster. To raise our body temperature, all our body has to do is regulate how much energy is being lost to the atmosphere versus how much energy is staying in the system (our body); which it can do in all sorts of ways.

2

Nfalck t1_iuhzm38 wrote

Thank you! So the hypothalamus induces the fever primarily by reducing heat loss, e.g. by reducing blood flow to the skin surface and cutting off the sweat response, rather than increasing mechanical or chemical thermal generation? Or is it more of "there are lots of processes in the body that contribute to heat generation and heat loss, and the hypothalamus pulls all of them simultaneously?" Or is it that there are so many interrelated processes that it's not clear exactly which levers the hypothalamus is pulling, we just know that heat generation increases and heat dissipation becomes less efficient?

5

InfernalOrgasm t1_iui0e0h wrote

We have a pretty good idea of how the immune system works; but we know less about how it works than we do know how it works (as far as we know). It's mostly reducing the amount of thermal energy lost, but doing "more work" does inherently increase thermal energy. So it's probably a balance of all of that.

Here's a good YouTube channel that covers quite a lot of the immune system in a very layman's kind of way.

1