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Why Salt Makes You Thirsty

Why does eating salty popcorn or baked ham make you thirsty, sometimes a few hours after you've eaten it?

A spilt salt skaker

Photo: ladybugbkt (Flickr)

As saltier blood goes through the body, it makes the fluid outside of the body cells saltier than the fluid inside the cells.

Let’s follow salt into the digestive system and see what happens. In the wall of the small intestine, the salt is absorbed into your bloodstream, making your blood saltier than it was before.

Salty Circulation

As the saltier blood circulates through the body, it makes the fluid outside of our body cells saltier than the fluid inside the cells.

The cells notice the change right away. That’s because the extra salt outside acts like a magnet, pulling water out of the cells. The cells try to hold in the water and they send chemical messengers to the brain, protesting the saltiness of the fluid around them.

Thirst Center

There are also sensors in the thirst center in the brain that keep tabs on the saltiness of the blood. When the thirst center goes on alert because things are too salty and the body needs water to dilute the salt, that’s when you start to feel thirsty.

The kidneys help dilute the salt too by slowing down urine production and conserving water. The constant balancing of salt and water in the body helps maintain the right amount of water in our cells and in the bloodstream. That controls our blood pressure.

  • nadwa

    is that really why you get thirsty???????

  • nadwa

    is that really why you get thirsty???????

  • camillapowel

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  • kelsey alterio

    This is dumbed-down science for the [lack of a better term] uneducated. No mention of osmosis? This is not science.

  • summer_song

    A good teacher can take the most complex subject and make it so a child can understand it. Nothing wrong with leaving out the names of the processes for a basic explanation.

  • Maci Hill

    Theirs no use of osmosis, diffusion, higher concentration, lower concentration, cell membrane, and semipermeable. How is this science at all

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