What is Thirst? Definition of Thirst | Thirst Mechanism

What is Thirst? Well, are you interested to know the actual definition of thirst? Thirst is usually a desire to drink various potable liquids, resulting in over the basic instinct of animals to drink. It is an essential mechanism involved in fluid balance. It arises from a lack of fluids or an increase in the concentration of certain osmolytes (compounds that affect osmosis ), such as sodium.

If the body’s water volume falls below a certain threshold or the osmolyte concentration is too high, structures in the brain detect changes in blood components and arouse thirst. Dehydration continues can cause acute and chronic diseases but is more often associated with kidney and neurological disorders.

What Is Thirst

The excessive thirst called polydipsia, along with excessive urination, called polyuria, may be an indication of diabetes. There are receptors and other systems in the body that detect a decrease in volume or a higher concentration of osmolyte. Apart from this information, let’s learn about what is thirst deeper now.

What is Thirst?

Some sources distinguish “extracellular thirst” from “intracellular thirst”, where extracellular thirst is thirst generated by decreasing volume and intracellular thirst is thirst generated by increasing osmolyte concentration.

thirst mechanism in brain

When is it normal to be thirsty?

It’s normal to feel thirsty after eating spicy foods or doing strenuous exercise, especially in hot weather. However, sometimes the thirst is stronger than normal and continues after drinking. You may even experience blurred vision and fatigue. These are symptoms of excessive thirst, which may indicate a serious underlying medical condition.

Causes of Excessive Thirst

The Causes of excessive thirst that can include were as follows.

  • Eating salty or spicy foods
  • Disease
  • Intense exercise
  • Diarrhea
  • Vomiting
  • Burns
  • Significant blood loss
  • Certain prescription drugs, including diuretics and certain antipsychotics

Excessive thirst or thirst that cannot be quenched can be symptoms of serious medical conditions, such as:


what is thirst mechanism

What is Thirst? When does the Dehydration encounters? This occurs when the right amount of fluids is lacking for the body to function properly. Severe dehydration is life-threatening, especially for babies and young children. Dehydration can be caused by illness, excessive sweating, too much urine output, vomiting, or diarrhea.

Diabetes mellitus

Excessive thirst can be caused by high blood sugar (hyperglycemia). It is often one of the first noticeable symptoms of this type of diabetes.

Diabetes insipidus

This form of diabetes occurs when the body cannot regulate fluids properly. This causes an imbalance and loss of water in the body, leading to excessive urination and thirst.

Dipsogenic diabetes insipidus

types of thirst in psychology

This condition is caused by a defect in the thirst mechanism, resulting in increased thirst and fluid intake with frequent toileting.

Heart, liver, or kidney conditions.


This is a dangerous disease caused by a severe inflammatory reaction from an infection with bacteria or other germs.

What if You Feel Always Thirsty?

What is Thirst? What are the reasons behind it? Other reasons why you may be more thirsty than usual include the following. Let’s go through each in a brief.

What if You Feel Always Thirsty

Dry mouth

When your mouth feels very dry, you may feel thirsty. It usually happens because the glands in the mouth make less saliva. It can be caused by medications you take, treatments for other conditions such as cancer, diseases such as Sjogren’s syndrome, nerve damage in the head and neck, or tobacco use.

If your glands don’t make enough saliva, you may have other symptoms, such as:

  • Bad breath
  • Taste change
  • Irritated gums
  • Lipstick sticking to teeth
  • Thick, stringy saliva
  • Chewing problems


It means that the body does not have enough healthy red blood cells. Some people are born with anemia, while others get it later. There are many things that can cause it, including illness, a poor diet, or heavy bleeding.

types of thirst

Mild anemia probably won’t make you thirsty, but you may need more water if the condition worsens.

Other symptoms include:

  • Dizziness
  • Feeling tired and weak
  • Have pale or yellowish skin
  • Rapid pulse
  • Perspiration

Excess Salt in the Diet

thirst receptors

Salt draws water out of your cells and forces your body to conserve as much water as possible, so you urinate less when you eat too much salt. The cells send a chemical message to the brain asking for more water, and you begin to feel excessively thirsty. Reduce your salt intake and make sure you drink enough water.

Spending too much time in the sun

When summer arrives, you spend more time outdoors, whether it’s in a park, on a beach, in the mountains, or in your backyard. Even if you are not running, you can become dehydrated, especially in sunlight.

If you know that you will be out all day, make sure you have a bottle of water handy, especially if you go to the mountains for a walk or to the beach to bathe and play in the sand.

Not Drinking Enough Water

The number one cause of always being thirsty is not drinking enough water. As a good rule of thumb, drink a glass of water with every meal and two between meals. If it helps, set an alarm on your phone and make it go off once every two hours.


I guess the details related to what is thirst or thirst mechanism shared here are very much understandable. To learn more interesting details which you really unaware of, be in touch with the best water purifier reviews and acquire the needful information within a small time period.

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