How Long Can You Survive Without Water And Why?

logo by Editorial Staff | Updated on July 30th, 2022

3 days is the exact answer.

Our bodies require a certain amount of water to operate properly, and a person may only last a few days without it.

dusty desert valley

Many other significant elements, such as a person’s activity level and environment, also play a role, so it’s impossible to predict how quickly a person will die from dehydration.

Dehydration occurs quickly, resulting in acute thirst, weariness, organ failure, and death. On the first day without water, a person may feel thirsty and slightly lethargic and end up with organ failure by the third.

Dehydration does not impact everyone in the same way.

Each living being has a different tolerance threshold for dehydration and should be prepared to go without water for longer or shorter periods than others.

What is the significance of water?

Thirst is a survival instinct, and I’m sure you’ve recognized by now that water is one of the most important nutrients living creatures require. Water maintains our body temperature, promotes digestion, and aids in waste disposal. It is also required by the brain to generate hormones and neurotransmitters. So… it’s rather significant. Clearly.

Water is the most abundant molecule in our bodies, accounting for more than 65 percent of the liquid volume. After the water from external sources is depleted, the body utilizes the water stored in our fat cells to quench its thirst.

Camel can survive without water for days in the desert heat by extracting water from fats all over their bodies. Unfortunately, the human body does not have as much storing capacity.

After a week without water, sweating stops, causing an inevitable rise in body temperature, and digestion becomes difficult owing to a lack of saliva or digestive secretions. At the same time, blood pressure falls due to reduced blood volume.

Death is just around the corner in such deplorable circumstances. Surviving without water boils to upsetting the delicate balance between losing and gaining water. This indicates that survival can be extended if the pace of losing water by sweating, peeing, or quickly exhaling is less than the rate of gaining water through food and beverage consumption.

How long can you go without drinking water?

You can last three days without water. However, this figure varies greatly based on personal and environmental conditions. A young, healthy individual is considerably more likely to live without water than an older adult with health problems.

Personal characteristics that might influence how much water you require include:

  • Age: as you age, it becomes more difficult to regulate your body temperature, so you may need to drink more water to support this process. 
  • Health: your overall health can impact how much water you require. Unhealthy people may require extra water to keep their important health processes working efficiently.
  • Weight: Obese persons have a higher body mass index (BMI), making them more prone to dehydration. As a result, they require more water to compensate. 
  • Gender: women require less water than males. Therefore they can go longer without it.

The following environmental conditions influence how long you can survive without water:

  • Heat: many of us see someone is living without water as being stranded in the desert, traveling endless dunes, and assaulted by a hostile sun. Because we lose so much water via sweat—around three to four liters per hour when paired with exercise—heat plays a significant role in dehydration. This is a formula for catastrophe for someone who does not have access to water.
  • Humidity: as bizarre as it may sound, excessive humidity can dehydrate us since it makes it more difficult for our bodies to cool down. And the dry air we breathe during low humidity periods might deplete our fluids during breathing. The humidity must be exactly perfect.
  • Altitude: high elevations disrupt our fluid and electrolyte balances, necessitating increased water consumption4.
  • Food intake: if you have access to water-rich foods such as apples, watermelons, and peaches, you’ll require less water to survive.
  • Activity levels: because exercise causes us to sweat, you’ll need more water to rehydrate if you’re tramping up and down hills.

How Long Can You Go Without Drinking Water?

Individual and AgeAmount of Water Intake
Children, =4 to 8 years5 Cups
Children, =9 to 13 years7 to 8 Cups
Children, =14 to 18 years8 to 11 Cups
Men, =19 and >19 years13 Cups
Women, =19 and >19 years9 Cups
Pregnant Women10 Cups
Breastfeeding Women13 Cups

Why would you go that long without water?

Water is essential to a well-balanced diet since the body needs it to function. Water makes up about 70% of the human body.

Water is responsible for the chemical activities that occur in the body. Water aids digestion, aids in nutritional absorption, allows for biological mobility, eliminates toxins, and regulates body temperature.

It is possible to become quite ill if you do not drink enough water. Severe dehydration can cause dizziness and even collapse.

If someone exhibits signs of dehydration, they should drink water quickly and seek medical attention if they do not feel better.

People over 65 are at a higher risk of dehydration since they naturally feel less thirsty, and their kidneys may not operate as effectively.

Patients taking laxatives or diuretics cannot walk around to grab a drink. This makes it difficult for these people to keep hydrated.

Natural Water Loss

Food and water are necessary for human survival. A human can survive far longer without food than without water. Why? This is because water makes up a large portion of our bodies. Every day, we lose a lot of water.

Humans lose around two to three liters of water daily from bowel movements, urine, regular breathing, sweat, and household activity. The amount of water you require each day is determined by various variables.

Age, body fat, gender, health, and geographic region influence this.

Women require between 2 to 2.7 liters of water per day, while males require between 2.5 and 3.7 liters.

When we don’t drink enough water and lose it regularly, our bodies go into war mode.

What happens to your body when you do not drink enough water?

Your body is extremely sensitive to the amount of water you ingest. Based on your thirst sense, you most likely get enough water in your body. If you drink when you’re thirsty, your body is probably getting enough water regularly.

Your body’s processes will change if you don’t drink enough water. Your cells will shrink if you don’t drink enough water. Your brain will tell your body to urinate less frequently. This will happen via your kidneys. To work effectively, they require an appropriate water intake.

Without adequate water, the kidneys use more energy and cause tissue deterioration. To eliminate waste from your blood, your kidneys must operate properly. Your kidneys will eventually stop working if you don’t drink enough water. Other organs in your body may also stop working if you don’t drink enough water.

Other biological processes will suffer as a result of a lack of water. Without sufficient water intake:

  • Your body temperature will not remain stable.
  • Your electrolytes will be out of whack.
  • Your joints may not function correctly.
  • Your brain might enlarge.
  • Your blood pressure may rise or fall.

Dehydration Signs and Symptoms

As previously stated, water accounts for around 60% of your body weight. According to studies, losing just 3% of this weight through water loss might cause dehydration symptoms.

One of the first indicators of dehydration is that you pee less because your brain has instructed your body to do everything it can to preserve water. As a result, renal problems develop.

Other signs of dehydration you may experience after a day or two of water restriction are listed below.

  • Headaches; 
  • fatigue and sluggishness; 
  • elevated or fluctuating body temperature; 
  • dizziness and disorientation; 
  • heat cramps and heat strokes
  • The gradual weight reduction;
  • Joint stiffness and discomfort;
  • Oscillating blood pressure with abrupt shifts to the low/high extremes; 
  • Swelling brain; 
  • hallucinations 
  • Seizures

If your body loses up to 3% of its water, you will feel moderate dehydration, which may be treated with oral rehydration (water, foods, or rehydration medicine). Doctors typically prescribe the latter after severe bouts of vomiting or diarrhea.


Hydration is a vital need for human survival. Some people can last for weeks without food, but they can only go for a few days without water. Dehydration may be prevented by eating foods that keep the body hydrated and drinking plenty of water.

Dehydration may quickly impact the body if it is not replenished with water. Depending on the individual’s environment and effort, they may experience changes in their body as soon as a few hours. When someone has diarrhea or vomiting, their body loses water more quickly. A person who drinks water when thirsty is not at risk of dehydration.


Editorial Staff

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