Why when you drink water when you’re really thirsty you feel better/hydrated instantly but in that moment hydration hasn’t even started?

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Why when you drink water when you’re really thirsty you feel better/hydrated instantly but in that moment hydration hasn’t even started?

In: Biology

17 Answers

Anonymous 0 Comments

I suspect the immediate relief sensation is to help prevent water intoxication. It’s possible to drink enough water to throw off your electrolyte balance, which eventually disrupts your brain and muscle function. Drinking 3-4 liters of water in an hour can lead to death in a healthy adult.

Anonymous 0 Comments

The brain rewards you for behaviors that keep you alive. When the brain notices that you need water, it triggers the “thirsty” signal. As soon as you drink something, the brain rewards you for what you did and gives you that “ahh, hydration” feeling. What matters to the brain is that you actually did the life-preserving action, no need to wait and see whether the drink actually hydrated you.

Anonymous 0 Comments

You likely started to feel thirsty when your mouth was dry. The second you take a sip of water, your mouth is no longer dry and you feel relief.

Anonymous 0 Comments

There are sensors in your mouth that detect when you consume something. You and your brain know that water has entered and doesn’t need to send thirst signals.

People use this trick to knock thirst while wrestling by spitting water out so they can knock thirst and not have water sploshing around in their stomachs.

Anonymous 0 Comments

Here’s something cool to know even if it’s a tangent from the poster’s question: hydration already began before you even drank the water.

Water balance in the body is mainly controlled by a hormone called Vassopressin [or AVP]. Basically, this hormone is released from the brain when the body is either low in volume (hypovolemic or hypotensive) or too “salty” (or high in electrolytes). What it does is it reabsorbs water in the kidneys to combat dehydration. Since kidneys function 24/7, there’s always water to reabsorb.

The brain releases this hormone at a lower threshold compared to the brain recognizing the body is thirsty. So, even without realizing you’re thirsty, the body is already reabsorbing the water your kidneys are filtering.

Anonymous 0 Comments

Studies have shown that the gut bacteria colony can communicate directly to your brain. When you appease the gut-gods, they can send positive feeling signals to your brain. I presume the stomach itself can also sense the lack of water and do the same.

Anonymous 0 Comments

I’ve definitely noticed near instant minor effects from putting various things in my mouth, food, drink, drugs or what have you, etc

not sure if it’s the capillaries in the mouth absorbing some and sending it straight to the brain in one or two pumps, or some quantum smelling type mechanism or what

Anonymous 0 Comments

The moment you drink water, your sense of taste tells the brain more water is incoming and it actually releases some water early to flush the system, mostly from your fat reserves, which also double as water storage.

This is one of the functions your sense of taste has. Your body will also release glucose and fat early when you eat, before digestion kicks in, knowing reinforcements are on the way, to get you powered up and moving quicker than you might otherwise.

Anonymous 0 Comments

It’s like Pavlov’s dogs salivating when they hear the bell even though they haven’t been served food. Your brain has associated relief with getting water, and delivers it before the hydration once the association is established.

Anonymous 0 Comments

If your brain waited until the water got into your system to stop telling itself it’s thirsty you’d keep drinking for the next hour and you might hurt yourself.