Dehydration: 12 Symptoms Explained

Water is absolutely necessary for survival. It makes up approximately 60 percent of the human body, with every system depending on water to function properly. or the lack of water in the body has many repercussions. Some are not as glaring as the others but can pose a danger, nonetheless.

On any given day a normal person will lose 64 ounces of water through perspiration alone.

Sans exercise, most of the perspiration goes unnoticed. But the body is in a continuous process of regulating its temperature through sweat.

Similarly, even sitting in a chair or using the computer, the body is still working on maintaining a healthy core temperature.

dehydration symptoms

What is dehydration?

Dehydration, simply put, is a lack of water in the body. It occurs when more water is leaving the body than coming in. Water constantly leaves the body, mostly through sweat, urine, and stools. It is also a condition where an individual can no longer function normally due to fluid loss.

Every single cell in the human body needs water to function properly. Water regulates temperature, cushions and protects joints and organs and helps digestion move smoothly, to name a few.

What are the causes?

can be caused by any of the following:

  • Illness
  • Medication
  • Excessive sweating, urination
  • Hot temperature or weather
  • Not drinking enough water

Signs and Symptoms

1. Increased thirst

In order to work well, the body needs water. Thirst is the body’s way of telling that it is running low on water.

The sensation of thirst is felt because the lack of water can alter the balance of salt in the blood. This imbalance causes a cascade of effects that result in the desire for hydration.

Increased thirst is the main symptom of dehydration.

Polydipsia is the medical term that refers to increased or excessive thirst.

Increased and excessive thirst is when thirst becomes stronger and does not alleviate even after drinking water. causes the body to lack the proper amount of fluids for it to function properly. 

triggers the body’s thirst response.

Therefore, when thirst is felt, is already setting in. In many experiments, just 1 to 2% of dehydration has been shown to trigger thirst.

2. Dry mouth

Dry mouth is described as a burning sensation or feeling of soreness in the mouth. It can also alter the sense of taste. Some people also report experiencing some level of difficulty in speaking, eating or swallowing. Dry mouth can also make the mouth feel sticky.

In addition, dry or chapped and cracked lips can also be linked with dry mouth.

The clinical term for dry mouth is xerostomia.

The difficulties associated with xerostomia are also due to the lack of saliva production in the mouth. There is not enough amount of saliva to keep the mouth wet.

This stems from the lack of fluids in the body.

Among the symptoms of dehydration, dry mouth is one of the most common and easily reversible.

3. Bad breath

This is one of life’s most common annoyances.

Also known as halitosis, it is typically caused by bacteria that gather in the mouth. Bad breath is also one of the symptoms of dehydration.

In a healthy mouth, the saliva keeps the mouth moist and less hospitable for bad bacteria. Saliva keeps the bad bacteria away from the decomposing cells and food particles in the mouth. It can also help maintain the pH levels of the mouth.

When a person is dehydrated, saliva production decreases. The mouth loses out on its antibacterial function. The bacteria that live in the mouth tend to multiply as the mouth dries out.

Bacterial overgrowth then gives way to bad breath.

4. Craving sweet food

Craving for sweet food is one of the unknown and unusual symptoms that a person is dehydrated.

Lack of water consumption is often mistaken for sugar cravings and hunger pains. Instead of actually making the body crave for water, masks itself as hunger. This is because thirst and hunger cues are associated with the same area of the brain – the hypothalamus.

A lack of fluid intake can make it more difficult for the body to metabolize glycogen (stored glucose) for energy. This makes the body crave sugar to provide a quick source of energy when, in fact, it’s actually water that it needs.

Glucose is a major source of fuel for the cells, and water helps facilitate this process. A lack of fluids can cause difficulty in the production of energy output and can trigger sugar cravings.

due to exercising, in particular, can also cause sugar cravings. It is likely because the body has used up some of the glycogen. This makes a person crave carbs and the quickest way to get them is in the forms of sugary foods.

In addition, can also interfere with serotonin levels. Serotonin is the “feel-good” hormone. This can trigger sweet cravings as well.

5. Muscle cramps

A muscle cramp is a symptom that most people do not normally link with dehydration.

It is, in fact, closely tied to the loss of fluids in the body. Fluids that help muscles contract and relax and keep muscle cells hydrated and less irritable.

Muscle cramps are the sudden, strong and painful tightening or contracting of the muscles. It may come suddenly and lasts for a few seconds to a few minutes.

Vigorous activities like exercise can cause excessive fluid loss through perspiration and may lead to dehydration. It is also more likely to happen on hot days when the body sweats a lot to keep cool.

depletes electrolytes and other minerals in the body. The muscle cells require enough water, glucose, sodium, potassium, calcium, and magnesium to allow the proteins within them to develop an organized contraction.

In addition, a low supply of these can cause the muscles to cramp or spasm.

6. Decreased urination

Not peeing often is an alarming symptom of dehydration. This is usually a sign that the body is severely dehydrated. Immediate medical attention is needed if this is the case.

Oliguria is the medical term used for decreased output of urine.

The body works to retain fluids lost by decreasing urinary output when it becomes dehydrated. The kidneys will try to retain as much fluid as possible and peeing less often than usual is a sign to increase hydration intake.

The whole body will essentially try to conserve water if it can’t replace the fluids that are getting lost. 1-2% of water loss can be tolerated by the body but anything more than that will present problems.

Oliguria can also be dangerous because the body isn’t getting rid of toxins. It could lead to other health problems like kidney stones. This is a condition in which also often plays a big role.

7. Dark yellow and strong-smelling pee

Dark yellow urine is one of the most common indications that a person may be dehydrated. Of all the dehydration signs, this may be the easiest to spot, since all it takes is a glance down into the toilet or urinal.

Normal urine should be pale yellow in color, like lemonade. If urine is a darker color, like apple juice, this could be a sign of moderate to severe dehydration.

A darker urine color means that there are not enough fluids coursing through to properly flush the toxins from the system. 

Dehydration is the most common reason for dark urine, but it is usually easy to treat. When the body loses more water than it takes in, it will start to hang on to the water it has.

Minerals and chemicals in urine become more concentrated and deeper in color because there is less water to dilute them.

8. Skin elasticity

The body is made up of at least 60% water, and for the skin, hydration is very important. About 20-30 % of the skin consists of water.  Hence, dry skin is a symptom that a person may be dehydrated.

On the other hand, when the body is dehydrated, fluid is pulled away from the skin and diverted to major organs to carry on with more important processes. This shift of fluid away from the skin causes it to lose its elasticity.

It is important to note, though, that dehydrated skin and dry skin are not the same. However, it’s important to make clear distinctions.

Dry skin is caused by the body not producing enough of the natural oils that the skin needs. Whereas dehydrated skin is caused by the lack of water in the skin cells. Dehydrated skin may appear dry.

Dehydrated skin is characterized as feeling rough. It may also cause some itching. When the skin lacks hydration it also may have severe flaking, scaling or peeling.

In addition, the skin may also exhibit lines or cracks that if deep enough may cause some bleeding.

9. Headache

Headaches are one of the most common types of pain that can be a symptom of many health conditions. It can even indicate if a person that they may be dehydrated.

When the body loses water faster than it can be replenished, it can lead to problems including unpleasant dehydration headaches.

Dehydration can make the brain to temporarily contract or shrink from fluid loss. This process causes the brain to pull away from the skull. This then brings pain and results in a dehydration headache.

This kind of headache can be dull or intense migraine-like pain. It can occur at the front, back, side, or all over the head.

10. Rapid heartbeat, palpitations

Rapid heart rate or heart palpitations are two other symptoms of dehydration.

Palpitations feel like the heart is jumping or skipping a beat.

Interestingly, these symptoms are a result of the heart attempting to compensate for the lack of fluid in the body.

The volume of blood in the blood vessel decreases when there is not enough fluid in the body. The body then works harder to deliver enough blood to the different organs by increasing its heart rate. This increase pumps more blood throughout the body.

As a result of this, a person may feel as if their heart is racing, fluttering or pounding extra hard.

Fortunately, in most cases of dehydration, this increase in heart rate effectively makes up for the low blood volume.

However, if dehydration becomes severe, the heart will have a hard time compensating for the lack of fluid. If the organs are unable to get blood from the heart, they will eventually shut down.

11. Fatigue or lethargy

Fatigue is a common dehydration symptom, and it’s said to be the most common cause of midday fatigue.

Dehydration can make blood pressure drop which, in turn, creates a decrease in blood flow to the brain. This causes fatigue and lethargy.

Without adequate hydration, the body can experience muscle soreness, longer recovery times and less drive to push oneself.

For the most part, as little as 3% of lost water weight due to dehydration can cause as much as a 10% drop in performance level.

Dehydration can also affect the sleep hormone, melatonin. Lack of hydration can gradually reduce levels of essential amino acids which are needed to produce melatonin, throwing off the circadian rhythm and making it harder to stay asleep.

12. Confusion, dizziness, fainting

The brain is composed of 73% water. That being said, it means dehydration can have a significant effect on brain function.

Lack of fluids can put stress on cognitive functioning. mild dehydration can cause irritability and decreased brain function.

There are also a few studies that discovered that a 1- 2% body fluid loss can cause anxiety, moodiness, difficulties with concentrating and a decline in short-term memory.

Furthermore, brain function can deteriorate significantly as dehydration becomes more severe. Severe dehydration can cause confusion and incoherence.

Hydration is essential in regulating blood volume, including blood pressure. If dehydration is present, blood pressure tends to decrease which often leads to dizziness and lightheadedness.


Water is a very important part of life. human beings can survive for almost three weeks without food but can only last days without water? Clearly, water is very essential for survival.

Experts say the exact amount of water needed to drink every day can vary based on climate, activity level and even medication usage since some medicines can cause dehydration.

Furthermore, staying properly hydrated has many additional benefits like promoting healthy weight management, increased brain power, maintain heart health, toxin regulation and even taking the edge of hangovers.