Recent comments in /f/askscience

Shadowfalx t1_j961xa3 wrote

Reply to comment by Mercerskye in Why are fevers cyclical? by Key-Marionberry-9854

This is the worst kind of amateur take.

Humans have generally had a few days to weeks of fat reserve plus some extra weeks with muscle. The calorie cost of raising your temp 4°F is low. Plus, we have, since becoming human and probably long before, lived in groups (often familial) that help each other.

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FiascoBarbie t1_j960udv wrote

Reply to Why are fevers cyclical? by Key-Marionberry-9854

A very high fever can kill you in a fairly short amount of time in pretty nasty ways. You can go for weeks without eating. If you are staying hydrated and have no antibiotics or antihelmetics or anti malarials etc the slight increased calories (really, did you do the math?) is a no brainer against whatever immune benefits you get from killing off what is likely the major source of death until recent times (infections). This is very much forward momentum in the survival game.

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Y34rZer0 t1_j95zjtx wrote

Reply to comment by DeftTurnOfPhrase in Was reading something related to Rock Salt mining. In places like the Himalayas where rock salt mining is done in cold temperatures, a lot of miners report burns. Why is it so that salt burns in a colder surroundings? Would it be the same reason why the salt ice challenge was so dangerous? by vvdmoneymuttornot

just like glitter clumping, it’s a common stripper problem.
Well that’s what my Nan used to say

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FiascoBarbie t1_j95yhai wrote

Reply to Why are fevers cyclical? by Key-Marionberry-9854

It is worth noting that not all fevers are cyclical.

It is also worth noting that not all fevers are related to viruses, In fact, as much as you can generalize, viruses are less pyrogenic than bacteria or other parasites.

It is also worth thing that while chills and sweats may cycle, this is not related to core body temp in any consistent way.

One of the reasons why chills and sweats alternate is that pyrogens alter the actual temp set point in hypothalamus . So it is more akin to setting your thermostat on your central heating to 80 and setting your AC to be at 80 also.

It is also worth noting that in many bacterial infections that cause fevers, some or most of the pyrogens are released by your own immune system , these are not really related to bacterial reproductive cycles in many cases in any functional way.

So a lot of people here are explaining phenomena that don’t really occur are are not occurring the way they describe.

Malaria has truly cyclical fevers that are related to the blood levels of parasites .

However, people who survive malaria and have cleared infections often have periodic fevers.

Before antibiotics, many people who once had some kind of fever and survive, often had periodic fevers for most of the rest of their lives, in a way that would also be unrelated to cycles of parasite reproduction the way people are talking about it here. The biographies and autobiographies of the colonial era explorers and geographers and botanists are useful in this regard.

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lunchlady55 t1_j95wnw2 wrote

Reply to comment by DeftTurnOfPhrase in Was reading something related to Rock Salt mining. In places like the Himalayas where rock salt mining is done in cold temperatures, a lot of miners report burns. Why is it so that salt burns in a colder surroundings? Would it be the same reason why the salt ice challenge was so dangerous? by vvdmoneymuttornot

Not Morton Salt with it's anti-caking agent Calcium Silicate!

When it rains, it pours!

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Celegantly t1_j95ur8e wrote

Reply to comment by mumtathil in If a human being is bleeding internally say in their mouth or stomach would they still have a risk of anemia? by Robbeee

Absorption is actually better 30 minutes to 2 hours before food, not with food. If patients cannot tolerate the GI side effects they can take it with minimal food. But especially not with caffeine, milk, high calcium foods, or anything high in fiber.

You absolutely want to take the pills with orange juice, something high in vitamin c.

And although absorption percentage is low, the high dose of the pills means I absolutely see positive effects in terms of correcting anemias that outweigh the side effects.

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wewbull t1_j95tpui wrote

Reply to comment by fack_yuo in Why are fevers cyclical? by Key-Marionberry-9854

Sounds like a classical control feedback loop in engineering.

However if it was just this there'd be no reason the body wouldn't have developed some kind of hysteresis to "debounce" the system, latching the fever on for a period after the viral load drops to ensure the complete eradication of the virus.

I suspect the fever is expensive or damaging in itself. So the best system is something less drastic, but that might take longer to kill the virus.

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Lostnumber07 t1_j95so6r wrote

Reply to If a human being is bleeding internally say in their mouth or stomach would they still have a risk of anemia? by Robbeee

Yup. For anatomy purposes the lumen of the digestive tract is external the body(debatable I am sure). It’s a bit confusing but kinda makes sense considering the anus and mouth both open to the external environment. If you think about it a step further you also have blood in an area where it cannot deliver oxygen and remove waste, rather it gets digested. At this point the blood is not doing it job and the person can be considered anemic because low Blood levels are based of serum concentration.

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