What is Dehydration?


What is Dehydration?

Mild to moderate dehydration is commonly defined as 2-6% of body weight loss through fluid.

Certain conditions such as vomiting and diarrhea, heavy sweating, or lack of food and fluid intake can lead to inadequate levels of fluid and electrolytes within our bodies. This is called dehydration.

Our bodies require the correct internal balance of water and electrolytes to function correctly and remain healthy. Every day we lose fluid and electrolytes via urine, sweat, saliva, and other bodily fluids. Usually, a normal, healthy diet will serve to replace our lost electrolytes and fluid.

We lose fluid and electrolytes in four major ways:
  • Vomiting
  • Diarrhea
  • Sweat
  • Urine

The Function of Water and Electrolytes

Water accounts for a large percentage of our total body weight: 70% in infants, 60% in men, 55% in women, and 45% in the older population (> 65 years of age).

Water has several important functions in the body:

  • Helps maintain body temperature
  • Assists with digestion
  • Lubricates tissues and joints
  • Acts as primary solvent for the transport of nutrients and metabolites

Electrolytes (such as sodium, potassium, and chloride) are dissolved in the water in our body.


  • Help the body retain fluid
  • Are essential for nerve and muscle function
  • Are usually consumed in our food


Water and electrolytes move around the body constantly to maintain the correct balance. This allows the body to perform normal functions correctly.

The amount of water and electrolytes in our body at any one time is controlled by how much fluid we consume and how much fluid we lose daily.

Best Way to Manage Mild to Moderate Dehydration

The most rapid and effective way to manage mild to moderate dehydration is to activate the Sodium- Glucose Co-Transporter (or pump) located in the intestinal mucosa (enterocytes) of the small intestine. These special cells activate when they encounter the correct ratio of sodium and glucose in water. This causes the body to absorb these molecules and rapidly absorb water in the process.

This image illustrates how it works: