The fact that humans need a significant amount of water to survive is no new news. Dehydration can be deadly if extreme and can take place rather quickly: from thirst to organ failure to death. But the question is, how long can humans actually survive with no water? Hop in and let’s scroll through this article to find out!

Duration of survival without water

desert dune with blue sky

Water is an essential substance needed by our body to perform vital functions. As simple as keeping our cells alive requires a good amount of water. While answering the question requires consideration of a number of factors, a person can generally survive for around 3 days with no water. But as I’ve said, there are factors to consider such as:

  • Age
  • Lifestyle
  • Activity level
  • Overall health
  • Gender
  • Height
  • Weight

What an individual consumes also affects the amount of water they needs to drink. Someone who consumes food rich in water, such as juices, fruits, or vegetables won’t need as much water as someone who has been consuming bread, grains, and other dry foods. Additionally, the environment matters too! Too much perspiration results in water loss so they need more water intake. 

Effects of no enough water

Humans cannot last long with no water supply because our body needs water in most of the vital processes such as:

  • Body temperature regulation through perspiration and breathing
  • Digestion by forming saliva and breaking down food
  • Balancing the pH level of the body
  • Moistening of mucous membranes
  • Joint and spinal cord lubrication
  • Body’s utilization of hormones
  • Waste elimination through breath and urine
  • Transportation of toxins out of the cells
  • Oxygen delivery throughout the body

These are the very reasons why dehydration can lead to organ failure. Without water, the body is unable to produce sweat, and without sweat, there will be a dangerous elevation of body temperature. This may lead to blood volume drop causing decreased body circulation. These events may lead to a severe drop in blood pressure and ultimately, death.

Another series of events that can take place is that without water, the body cannot remove toxins from cells and excrete them through the breath and urine. The buildup of the toxins can affect the functioning of the kidneys negatively which may lead to the dangerous kidney failure.

Food and dehydration

Fruits and vegetables are water-rich foods that can help prevent or overcome dehydration. Conversely, if suffering from this problem, avoid dry foods such as bread, salty chips, and other dry snacks as they can make dehydration a lot worse. In addition to these, alcohol and caffeine may also promote dehydration because of their capability to cause excessive urination.

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 due to the fact that water makes up a large portion of our bodies. Every day, we lose a lot of water.

Humans lose approximately two to three litres of water each day through bowel movements, urine, normal breathing, perspiration, and household activity. The amount of water you require each day is determined by a variety of factors.

This is influenced by factors such as your age, body fat, gender, health, and geographic region.

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

When we don’t drink enough water and lose it on a regular basis, our bodies go into war mode.

Risks from dehydration

woman's hand on face

According to the Nutrients journal, thirst is the very first sign that signals a person that he/she does not have sufficient water in the body. Along with this, dry mouth can also occur. Water accounts for 60% of a person’s body weight and a 3% water loss will already jumpstart dehydration. If water is not readily available, the brain sends signals for water conservation. An example is by decreasing the function of the kidneys to decrease urination.

Signs and symptoms of dehydration are:

  • Headache
  • Lack of energy
  • Dizziness and confusion
  • Heat cramps
  • Heat stroke
  • Stiff joints
  • Raised or unregulated body temperature
  • Brain swelling
  • Seizures
  • Sharp changes in blood pressure
  • Shock 
  • Unresponsiveness

These are the reasons why you should consume water regularly! Without water, so much of our bodily functions become chaotic.

Last words

By now, you should already know how important staying hydrated is. As a general rule, one may not survive for 3 days without water. Make it a habit to drink water regularly and to consume foods that are rich in water. Happy hydration!