Why Is Water Important: Functions of Water in the Body

This article answers the question; why is water important? Additionally, it shows how to spot the onset of dehydration, and covers the best ways to increase the daily intake of water.

Why Is Drinking Enough Water Important?

Almost all biological functions require the presence of water to work well. The human body is composed of 60-70% water, which is hard to imagine at first glance. However, with some introspection, it becomes clear.
Cells are made primarily from fluids, these cells are surrounded by other intracellular fluids, and the blood is also water-based. This explains the high percentage of water in most mammals.
Water is responsible for three main functions:
  1. Transportation of substances within the body
  2. Waste disposal from the kidneys, liver, and lymphatic system
  3. Aiding in metabolic processes and temperature regulation

The Main Functions of Water in the Body

Water is critical to the proper functioning of the various physiological systems. Here are some of the main reasons why it’s that important.

Water Is an Integral Part of the Cardiovascular System

No analysis or extensive studies are needed to demonstrate that water is the main ingredient of blood. It’s a fluid that’s not too viscous, so it clearly needs consistent hydration to maintain its properties.

Water Is Essential to Food Digestion and Metabolism

Nutritionists have debated for a long time whether a person should drink water before, after, or during mealtimes. Several theories emerged advocating each stance, and an equal number admonished people who followed that advice.
Lately, the consensus seems to be ‘drink water at all times”. Food metabolism works best when the various enzymes are abundant and flowing unhindered. Also, it’s easier for food to go through the various phases of digestion if it is more on the soft than the solid side.
Hydration doesn’t necessarily come from water. Food with a high content of water, like most vegetables, is also a great source.
Finally, recent research showed that metabolism gets a boost with a higher water intake. Additionally, people seeking weight loss get a better result when their daily intake of water is high.

Water Helps the Body to Get Rid of Toxins and Wastes

The liver and kidneys have a tendency of concentrating toxins in the absence of water. It’s recommended to drink a sufficient amount of water to help the body in getting rid of unwanted substances.

Water Helps in the Absorption of Nutrients

Many vitamins, minerals, and food substances are water-soluble. The only way they can be absorbed inside the cells is by being carried along with water.
Balancing water intake with the amount of consumed nutrients doesn’t need to be an accurate chemical process. A person just needs to drink enough water, then the body regulates the whole thing for optimal results.

Water Assists in Temperature Regulation

This function is often glossed over, as most people miss the connection between heat regulation and water.
The way it works is through sweating. If the ambient temperature is high, or if a person has been exercising, the body temperature increases significantly. One way to cool off is through perspiration.
Along with that, the body also regulates its electrolytes, which is an extremely fascinating and complex matter. It also needs water to work.

Water keeps the Skeletal and Nervous Systems Healthy

Muscles contain more water than fat. This is an interesting fact. And to top that with more unexpected facts; the spinal cord and joints need quite a lot of water to function.
The synovial fluid which surrounds joints lubricates these spots and keeps them healthy. In the absence of that fluid, people often suffer from arthritis.
Additionally, the brain is more than 70% water. That’s why one of the earliest signs of dehydration are anxiety, fatigue, dizziness, and loss of cognitive function.

What Exactly Is Dehydration?

All living cells need water to stay viable and effective. And since tissues and organs are made up of cells, these too can’t function properly in the absence of water. Humans, and most mammals, are designed with water as the main component.
Dehydration doesn’t happen only when a person is stranded in the middle of a desert. People can easily get dehydrated if they spend a couple of hours out in the sun without drinking.
The effects and extent of dehydration are dependent on various factors like age, gender, health status, ethnicity, and other environmental conditions. Thus an adult fit man can spend two hours in a car on a hot day and just be inconvenienced. To a child, that is mostly life-threatening.
Dehydration manifests in several ways. Here are some of the common signs:
  • Feeling parched and thinking of water non-stop
  • Having dry lips, tongue, and throat
  • Feeling tired or dizzy
  • Infrequent visits to the bathroom
  • Dark-colored urine
  • Infants present with sunken eyes and flaccid skin

How to Increase Daily Water Intake?

Dehydration can occur to a lesser degree within the day if one is fasting, if the day is too hot, or if a person is suffering from diarrhea. Pregnant women who vomit frequently could also suffer from some degree of dehydration.
It’s essential then to remember to take a sip of water throughout the day. There are some online hydration calculators that estimate the recommended daily intake for each individual.
Here are some useful tips to increase daily water intake, even for those who aren’t big fans of the water bottle.
  1. Placing a pitcher of fresh juice on the table
  2. Adding fragrant herbs or a few slices of lemon to the water bottle
  3. Eating fruits and vegetables as snacks throughout the day
  4. Reducing diuretic beverages like coffee, tea, and carbonated drinks
  5. Cooling the water or adding a couple of ice cubes to the glass
  6. Drinking herbal teas occasionally
  7. Using an alarm to get a sip of water at regular intervals

When Is the Best Time to Drink Water?

Staying hydrated throughout the day is highly recommended. However, there are certain times that drinking water becomes essential.
Here’s a quick reminder of when it’s best to get a glass of water:
  • When a person is feeling thirsty.
  • Right after waking up
  • Around mealtimes (before and after)
  • Before and after exercising.
  • At regular intervals during intense, or long, exercise
  • If a person has a headache or feels depleted
  • In the evening to help in unwinding


Water is by far the most important substance that anyone consumes on a daily basis. It’s essential for the proper functioning of every biological system. Simply, because it’s a fundamental part of every living cell.
People need on average 4-8 glasses of water per day to stay healthy, which is not difficult at all. And the result is certainly worth the effort.