What does it mean to be thirsty?

https://www.quantamagazine.org/what-does-it-mean-to-be-thirsty-20250811/

by pseudolus • 12 months ago

159 106 12 months ago

JSR_FDED• 11 months ago

I have the opposite problem, after one glass of water I feel full and drinking any more makes me nauseous. It’s a struggle to get sufficient hydration during the day.

WalterGR• 11 months ago

How many ounces consumed over how many minutes?

noman-land• 11 months ago

Don't drink the whole glass at once?

jiggawatts• 11 months ago

Try adding a rehydrating powder mix, the same stuff they use for treating diarrhoea. It’s just salts, glucose, and citric acid. It is hugely more hydrating than plain water, with a much faster onset of feeling relief from intense thirst.

Sports drinks are basically the same thing, but with excess sugars for “energy” (and weight gain).

pazimzadeh3• 11 months ago

try carbonated water +/- lemon juice

ykonstant2• 11 months ago

A good choice if you have a carbonating machine; just take care of your teeth afterwards, especially if you add lemon juice.

move-on-by• 11 months ago

What are your thoughts on cows milk? There are a number of studies suggesting it’s better at hydration than plain water regardless of skim vs. whole.

voakbasda• 11 months ago

I own a dairy cow and milk twice a day. I drink a lot of milk. For me, it’s definitely not as good for hydration. And unless you skim it thoroughly (yuck!), it contains an obscene number of calories. It’s not a great substitute for water, but it tastes far better.

moi23882• 11 months ago

First off, it doesn’t have to be plain water. Secondly, the two liters a day was two liters of moisture, not drinking two liters a day; food is included in this amount

Steve442• 11 months ago

food is included in this amount

When my wife was ill a few years ago the doctor suggested Angel Delight[1] to help maintain fluids. Until then it hadn't occurred to me you're still effectively drinking half a pint of milk when you eat a bowl.

[1] It's an instant dessert / mousse that you mix up with milk. https://en.wikipedia.org/wiki/Angel_Delight

avalys4• 11 months ago

I'm so interested in this topic, for a weird reason.

Since I was a kid, I've thought I was "prone to migraines", and ascribed various triggers to them - sun exposure, heat, physical exertion, mental exertion, etc. I'd get a migraine sometimes after a long hike on a weekend - and also a long business meeting entirely indoors in an air-conditioned space.

Only when I was around 35, did I figure something out. All these situations lead to me getting dehydrated without any obvious accompanying feeling of thirst. Hiking all day will do it - walking around an outdoor shopping mall on a hot afternoon - or sitting in an all-day business meeting focused on the work at hand and forgetting to drink. And all these situations lead to a migraine - my only "migraine" trigger is simple dehydration, nothing more complicated.

The weird thing is, it took me a long time (decades) to put this together, because I just figured that I couldn't be dehydrated if I wasn't thirsty, and I had no association between "feeling thirsty" and getting a migraine.

I get what I consider normally thirsty in other circumstances, but somehow there's a failure mode where my body doesn't warn me. So now I just remember to chug lots of water (and electrolytes) if I'm exerting myself even if I don't really feel thirsty, and I can systematically avoid triggering migraines.

Now that I understand it the association is quite clear and obvious in retrospect.

zeta0134• 11 months ago

You might as well be my dream self writing a journal, because this describes my experience 1:1. It's kindof wild how long it took me to realize that I wasn't overheating at night due to the weather or the A/C being broken, but simply due to needing more water. That's one of my strongest signs as it turns out.

I don't know what "thirst" feels like at all! It's weird because I do feel hunger. If I forget to actually eat, my stomach kicks my brain and refuses to let me concentrate until I fix it. Hydration has no equivalent, and in retrospect, it's no wonder I was suffering headaches and nausea all through college on my diet of mostly soda. After I switched to water as my primary beverage things improved dramatically, but it's not perfect. I still have to watch the signs and pay attention, or I'll dehydrate myself by simply forgetting to drink.

tasuki3• 11 months ago

I don't know what "thirst" feels like at all! It's weird because I do feel hunger.

(I'm not an expert so take with a grain of salt)

This is it! Your hunger! It's actually thirst! When you're "hungry", try drinking a glass of water first. (Some people use this trick to lose weight, others, to stay hydrated...)

olup• 11 months ago

I can't relate more. I am also prone to ophthalmic migraines and have the same tendency to not be thirsty, to the amazement of the people I usually trek or live with. Only recently (35 and a kidney stone) did I gather that I might actually be in need of water even without feelings of thirst. I have never made a connection with migraines, and that might not be it for me but reading you makes me want to pay attention.

keeda• 11 months ago

Maybe a related point is that hangovers, of which headaches are likely the most common symptom, are caused in a large part by dehydration as well as electrolyte imbalance.

tasuki3• 11 months ago

A friend of mine always goes around parties and tells everyone to stay hydrated. It always feels completely out of place, and also it's saved me from many hangovers...

m463• 11 months ago

I just remember reading that adults start to lose their ability to sense thirst.

Wikipedia says 50:

In adults over the age of 50 years, the body's thirst sensation reduces and continues diminishing with age, putting this population at increased risk of dehydration.

https://en.wikipedia.org/wiki/Thirst#Elderly

tasuki3• 11 months ago

Tangential: I remember when I was a kid, adults always told me to drink more. Apparently I never drank enough, but I don't think it's ever caused me any problems. As an adult, I started drinking a lot of water - I drink easily 4 liters a day. Not even sure why. And now I always tell my kid to hydrate...

dghughes• 11 months ago

I'm 56 now and I'd agree. I bike in the summer for exercise and I drink while on the go as needed. I always got a headache after exercising. A regular headache not a migraine (never had one).

My discovery was Pedialyte it's meant for children but it's like the adult version or Gatorade. I drink it before I exercise and also drink as needed. I feel normal no headaches not dehydrated.

edit: I also have hypothyroidism so my hypothalamus must also be crap at regulating my thirst maybe?

williamdclt• 11 months ago

It's a big problem for the elderlies, it snowballs into serious issues. Don't feel thirst -> be dehydrated -> UTI -> hospital.

And having to be stay at a hospital for a length of time for any reason is very much Not Good for an elderly person. Other illnesses, muscle atrophy, disorientation, loneliness, cognitive decline...

walthamstow• 11 months ago

If my mum wasn't English she would have shrivelled and died of dehydration many years ago. There's a lot of water in 15 daily cups of tea.

IAmBroom• 11 months ago

Purely anecdotally, but I'm over 60, and have recently realized that I'm not as sensitive to dehydration feedback as I used to be. It's enough of a problem that I catalogued it as something to consider in my daily life.

Snacklive• 11 months ago

YES YES i get migraines and it's my body saying "Hey you need more water to function you know ?" usually i don't feel any thirst nor hunger, although, i do get hungry more often, but i can last a day without food before my head starts to hurt

lithocarpus3• 11 months ago

Same here - there are other feelings than a dry mouth or "feeling thirsty" that tell me I need more water. The slight beginning of a headache for example, or feeling a little bit dizzy, or many other things. I guess I could call these "feeling thirsty" since I now know when I feel these things that I probably need water and that's how I interpret them.

dazzawazza• 11 months ago

When I was in my 20s I realized I had lost the thirst signal. I never felt thirsty. I guessed this was because I lived a comfortable life and I had lost this signal in the noise of modern life.

So I set about deliberately retraining myself. I stopped drinking everything but water (and beer, because life) I'd exercise (and sweat) and then drink water. I retrained my body/mind to savour the pleasantness of drinking water when dehydrated and after a year of conscious effort I more or less recovered the sense of "thirst" and would pre-emptively desire drinking water.

We are pretty simple machines.

rootsudo• 11 months ago

It took me to teenagehood and then finally around the same time did I link it togtether.

Glad to know I'm not the only one and I do wonder how I missed this obvious step. Lately I've been doing electrolytes/water cliche of pocari sweat/etc and it really helps focus, weight, energy, etc.

arethuza• 11 months ago

I used to work for an industrial company that had a lot of plants which, by the nature of the work they did, were often extremely hot - a lot of them had urine colour charts in the toilets to try and warn people about dehydration.

Pooge2• 11 months ago

I think I have the same problem. I'm ever dehydrated now, but if I am I can tell something is wrong because my head starts to feel fuzzy (don't even know if it's the right word).

I used to get really bad migraines and a neurologist gave me a prescription. The only time I used it I felt like absolute shit. Never took another one.

Now I always have my 700ml flask with me.

kruffalon2• 11 months ago

I'm probably misunderstanding the article or you, but as I understand it you are talking about different things.

The article talks about the proportions between water and sodium, while you are talking about just filling up the tank with both.

I too drink water with sodium (and a few other salts) to relieve oncoming migraines but this has to be something else than the article is talking about.

kruffalon2• 11 months ago

Nvm, sitting with it for a bit I realise that when I drink salty water and it relieves my migraine my body needs either salts or water and by giving it both it takes what it needs and gets rid of the other.

thefz• 11 months ago

I just figured that I couldn't be dehydrated if I wasn't thirsty

When did you last pee and what color?

SneakyMission• 11 months ago

15 years ago, blue.

beingfit• 11 months ago

I just figured that I couldn't be dehydrated if I wasn't thirsty

This is what I learned, but from others online. I also learned that sometimes our body/mind may mistake thirst for hunger and we may end up eating some food instead of just drinking water (this is generalizing things a bit). This made me a little more aware of what I think of as hunger signals and I started tracking water intake (other than from food) everyday.

BTW, a tiny nitpick: it’s “led”, not “lead”, when you talking about the past.

avalys4• 11 months ago

As a stickler for spelling myself, I had to go back and check. I meant that sentence in the present tense as these situations continue to occur.

amelius• 11 months ago

I had a similar moment of enlightenment when I found out that depressive feelings can be caused by a lack of sleep.

lemonberry• 11 months ago

This 1000x. Anytime I get depressed my first response now is I need more sleep. Not to say that this is the answer for everyone, but yeah, I've noticed the same thing.

Nevermark• 11 months ago

I have a friend who recommends getting good sleep as the first step in solving any problem.

It is pretty nearly true.

geden2• 11 months ago

I also discovered that dehydration was a migraine trigger for me. I tend not to get big headaches now but get quite intense visual aura / disturbance.

Interestingly I also discovered that electrolyte supplements were also migraine triggers for me.

Leading me to think that electrolyte imbalance was the actually trigger. Caused by too little water increasing the concentration or added salts increasing it.

I tend not to feel thirst very strongly and think I do often confuse it with hunger.

I pay loose attention to urine colour as a gauge and make sure I drink plenty, kinda robotically when playing sports / walking in heat etc.

hackitup73• 11 months ago

A quick note for people responding, you might have a mild form of vascular dysregulation or flammer's syndrome. It can manifest as migraines and a decreased sensation of thirst, as well as other symptoms like cold extremities.

Afaik it's pretty harmless in general but it is associated with certain vision issues (normal tension glaucoma). Glaucoma is irreversible but has many treatment options especially if caught early. But you MUST go in for a (fast, cheap, painless) screening to catch it, it's really hard to detect unless there are issues otherwise. Please consider this if you really are showing a lot of these symptoms.

https://en.wikipedia.org/wiki/Flammer_syndrome

a_c• 11 months ago

I used to have warm and sweaty hands. Since I picked up bouldering I realised everyone is using chalk but I hardly sweat in my hands (I still sweat). My hands felt colder, and I don’t feel thirsty that if I don’t drink enough water it triggers headache. Took me quite some time to associate the headache with dehydration. Thanks for the reply. I will try to get myself a check up

avalys4• 11 months ago

How interesting!

I have had mild tinnitus my whole life (with no obvious lifestyle cause), and my migraines do often manifest as pain / pressure behind the eyelid. But I don't have any of the myriad other symptoms listed for Flammer syndrome - I sleep fine, my blood pressure is fine, I'm pretty solidly built (not underweight), I don't get cold easily, etc.

It is interesting to consider I might some sort of related disorder, though!

hansvm• 11 months ago

In activities prone to heatstroke, the advice is similar. Even for people with normal thirst detection capabilities, by the time that you realize you're thirsty it's likely too late. You need to be proactive about drinking enough water.

dkarl• 11 months ago

I grew up in a hot climate spending a lot of time outdoors, and I was educated about staying hydrated from a young age.

Still, like you, when I get symptoms of dehydration, I don't feel any intuitive connection with the need to drink, and I often don't feel any urge to drink at all. I have to remind myself to drink even though I don't want to.

It's weird. You'd think something so essential for life would have a better regulator.

bearl• 11 months ago

Notice peeing. That’s my hack. It can be used as a dehydration monitor, not just frequency and volume but color especially is informative.

jmmv• 11 months ago

Hah, same. I recently started getting many more back to back meetings than usual and, by lunchtime, I had a headache most days. It took me a while to realize that, while I’m at my desk, I keep drinking from the huge water bottle that I keep there, but when I go to meetings, I don’t. I started carrying the bottle with me (when I remember) and the headaches are gone.

17186274405• 11 months ago

When somebody complains about headaches, the first think my family does, and so now do I, is to ask whether you have drank enough. I thought this is common knowledge.

Next things are: sleep, sugar, stress.

SideburnsOfDoom• 11 months ago

There are simple indicators that can tell you how hydrated you are.

1) When did you last urinate, and was it a light or deep colour?

2) Can you make saliva easily in your mouth, or does your tongue rasp around?

That and "Have I had any water yet this morning / afternoon" keeps me hydrated.

krunck• 11 months ago

In my late 40's I realized I don't get thirsty. I did when I was younger.

I'm also a big sweater so I dehydrate quickly.

I found that I would get dehydrated to the point where my body tissues would reduce in volume or something and my Eustachian tubes would open up. They would either pop as I breathed or actually transmit my breath sounds directly into my ear from my throat. Concerning, yes.

Soon after drinking a lot of water this would go away. I soon realized that I was lacking a sense of thirst and was really stressing my body. Now I make drinking a habit.

pazimzadeh3• 11 months ago

Tangentially related, I'm curious to know why it is that proteins are so much more filling than other macronutrients (within minutes)

lithocarpus3• 11 months ago

One theory is that the most important nutrient that we really need a certain amount of every day is protein, and thus the body wants us to keep eating until it thinks we've got enough protein. (And for the vegans, I'm not saying meat - even most green plants and mushrooms are about 1/3 protein by dry weight). In nature almost every food has some amount of protein. If you get meat, you don't need to eat that much for your body to have all the protein it needs. If you are eating cake, it will take an awful lot of cake to have an adequate amount of protein.

In evolutionary past, if one had access to fresh fruit it might make sense to eat a lot of it right away since it won't keep, and the sugar in the fruit is easy for the body to store as fat and use later. In nature it's very rare to find a diet with very high fat and low protein but suppose you live by a macadamia tree, you may need to eat a lot of calories worth of macadamias to get enough protein. I have a feeling though that excess fat can go right through you in some cases like that - because there have been times where I was binging on peanut butter, like easily 16-24oz in a day often, like 2-3000 calories extra on top of my normal diet, and I didn't gain weight, I think a lot of it went through me undigested.

These are just hypotheses I'm not claiming they are necessarily the reason, and definitely are not the only mechanism involved as it's extremely complex. But they make sense as a simple place to start.

scythe2• 11 months ago

I have a feeling though that excess fat can go right through you in some cases like that - because there have been times where I was binging on peanut butter, like easily 16-24oz in a day often, like 2-3000 calories extra on top of my normal diet, and I didn't gain weight, I think a lot of it went through me undigested.

Nuts, specifically, do this:

https://www.nature.com/articles/0803735

https://www.cambridge.org/core/journals/british-journal-of-n...

Peanut butter is usually pretty bioavailable, though. Unless it was particularly coarse (like the kind you get freshly made at an upscale grocer)?

pazimzadeh3• 11 months ago

I meant how does the body know I'm eating protein so quickly (almost real-time)

scythe2• 11 months ago

I thought this was because the protein can (partially) neutralize stomach acid. Proteins contain an amino group which can be protonated; carbohydrates and fats do not.

rr808• 11 months ago

So dumb to see office workers sipping all day on their gallon water bottles, while outside the workers in the sun on the construction site taking the occasional sip.

dataflow• 11 months ago

So dumb to see office workers sipping all day on their gallon water bottles, while outside the workers in the sun on the construction site taking the occasional sip.

Dumb? People can't just drink their darn water as much as they please without getting judged now? What's your point?

dgan3• 11 months ago

not the OP but: it's fairly obvious that those office workers force themselves, so you can't say "as much as they please", otherwise they d stop 3 liters earlier. So yes, you will be judged.

It looks pretty dumb.

aredox• 11 months ago

It is still weird to see the health fad/moral panic/potomania in the US, about "drinking enough water". This is a borderline mania, that doesn't exist in other countries- including ones with hot climates.

https://www.menshealth.com/health/a60249105/how-much-water-t...

https://www.thrillist.com/drink/nation/do-americans-drink-mo...

https://www.delicious.com.au/drinks/article/why-we-so-obsess...

https://abcnews.go.com/Health/Wellness/waterlogged-america-d...

https://www.theatlantic.com/health/archive/2023/08/drinking-...

https://archive.ph/Y0W7e

No, you are not "chronically dehydrated". The rest of the world isn't, and you wouldn't be either if you drank "only" two liters a day instead of a full gallon.

This is one more symptom of that "freethinking" country that falls for every con.

PeterStuer• 11 months ago

I think it is more a comment about the insane size some of those beverage containers grew to over the years.

Some of them do indeed look like you could take a bath in them.

Then again, maybe their colleagues are using those as stealth biceps curl weights and are actually secret gym rats trapped at a desk.

NoPicklez• 11 months ago

How is that dumb? It could be that the construction workers are in fact dehydrated if that's the case

In my experience construction site workers have even larger jugs of water to drink.

poemxo• 11 months ago

I see blue collar workers carrying big hydroflasks all the time, I'm guessing they drink even more water.

Pooge2• 11 months ago

In all offices I worked in, less than 10% had their own water bottle. The others barely drank 2 cups per day. They go to the toilet at most twice per workday.

Baffling.

cedws• 11 months ago

People have this weird idea that you must drink a certain amount of fluid per day or be reminded to drink every so often. Like no, if you need water, you will be thirsty. If you feel the need to drink then drink, it’s not complicated.

geden2• 11 months ago

Well clearly it is complicated as this comment thread shows. Many people don't feel thirst because of age or other reasons or confuse thirst with hunger.

piperswe• 11 months ago

When I am in the heat, I do not feel thirst. I skip straight to heat exhaustion. I need to make a conscious effort to keep hydrated when I'm outside during the hot months.

mschuster91• 11 months ago

Back when I worked in heavy construction (aka, trench digging for telcos) I went through about six liters of soda a day when it was hot outside. And no, I was not diabetic, I was just very intensively working out!

The problem is, too many people in construction don't give a shit about their bodies. Corporate greed, incompetent/uncaring bosses, toxic masculinity, plain old incompetence and/or people "set in their ways"... these are the guys you see at age 50 with their spines shot, skin crumbling (or outright cancering out) and a plethora of health issues.

dgan3• 11 months ago

i can't stop eating the salt cristals before eating the lunch

The_Blade• 11 months ago

∑ Quanta Thirst

defyonce• 11 months ago

I am piloting a super sophisticated mech that is a literal home (primordial soup) for other tiny specs that cooperate together.

And more and more I ask this question. Why? There is only recursive answer, to copy itself, so the copy could continue piloting.

It is poetic and really weird.

layer8• 11 months ago

They should make an anime series about that.

trenchpilgrim• 11 months ago

They could call it "Diffusion Dave", or maybe "Jobs for Cells"

card_zero• 11 months ago

I am "fastened to a dying animal", at least you're proud of your fancy mech.

cobbzilla• 11 months ago

I recently learned that the inverse of thirst is called hyponatremic craving. This is when you have too much water and your body craves salt.

It ought to have a better word! “I’m feeling salty” doesn’t work!

Jarmsy• 11 months ago

That was one part of the article I found questionable- "If the body needs salt, those chips will cause a surge of pleasurable dopamine to flood the brain. If the body doesn’t need salt, that dopamine drip disappears"

Surely this second part is false? Most of us have got used to high levels of salt in modern diets, and prefer the taste of salty things even when we've had way more sodium than we need.

cwmoore• 11 months ago

Breaking and hauling concrete patios in the Florida sunshine, I learned to take a couple of salt tablets with my gallon or two of water per shift to prevent incapacitating symptoms of thirst. Gatorade was both not enough electrolytes and the sugar spike too quickly dissipated. On the flipside, distilled water strips excess ions.

mayama• 11 months ago

Same here. On recent Indian trips, I got hit with mild nausea after sweating in summer weather. I couldn't believe I wasn't able to go around like I used to few years ago. Had to bring along mildly salted water and take couple of sips now and then.

porridgeraisin• 11 months ago

This article reminded me to go drink water, I had forgotten.

prometheus76• 11 months ago

"However, animals like us do not experience salt desire as a powerful, controlling drive as we do with oxygen, food and water." (from the article).

I disagree with that, especially when I was young. I would crave salt. I would lick my hand and sprinkle salt on it, then lick the salt off. I would break chunks off the salt lick block we had for our horses. I would lick the homemade play-doh my mom would make because it tasted like salt.

There's no substantiation for the claim in the article that we lack a salt craving. Apparently, the author hasn't, but I know a lot of people that do.

What does it mean to be thirsty?

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