Overview

Your body is mostly made up of water. That makes fluids critical to your survival. When you do not replace lost fluid, it can be dangerous. This condition is called dehydration.

The most common causes of dehydration are:

• Sweating
• Vomiting
• Diarrhea

They cause the loss of water and electrolytes like sodium and potassium that help keep your heart working properly. Even a small loss of salt and potassium can cause an irregular heart beat and other problems.

You are at a higher risk of dehydration in hot weather or during vigorous exercise, when your body sweats to cool off. When you sweat, you lose fluids and reduce the amount of water in your body. Your blood volume and blood pressure drop. This can cause shock and organ damage to the kidneys, liver and brain.

You can also get dehydrated when you are sick with vomiting or diarrhea. Dehydration (usually due to diarrhea) is one of the leading causes of infant death worldwide. Children and the elderly also are at higher risk.

Dehydration often can be prevented. Every day, make sure you get enough fluids, especially in hot weather. Experts say you drink before, during and after exercise to stay hydrated. Drinking sports drinks can help you replace fluids and important electrolytes.

More on Dehydration