Summer Health — Dehydration

By Brooks Booker, M.D., ARC Anderson Mill
Board Certified in Pediatric Medicine

After a long walk, a morning run or a hard workout on a hot day, what's the first thing you do when you're finished? You probably drink a big glass of water.

Our bodies are about two-thirds water. When we exercise, we sweat, which causes us to lose some of the water that is needed for normal body function. If we do not replace the fluid we lose through sweat, we can become dehydrated.

When someone gets dehydrated, it means the amount of water in his or her body has dropped below the level needed for normal body function. Small decreases don't cause problems, and in most cases, they go completely unnoticed. However, losing larger amounts of water can sometimes make a person feel quite sick. To counter dehydration, you need to restore the proper balance of water in your body. First, you have to recognize the problem.

Signs of Dehydration

Thirst is one indicator of dehydration, but it is not an early warning sign. By the time you feel thirsty, you might already be dehydrated. Other symptoms of dehydration include:

• feeling dizzy and lightheaded
• having a dry or sticky mouth
• producing less urine and/or darker urine

As the condition progresses, a person will start to feel much sicker as more body systems (or organs) are affected by the dehydration.

Treatment for Dehydration and When to See a Doctor

Dehydration can usually be treated by drinking fluids with certain electrolytes which aid in rehydration. The type of electrolytes needed for rehydration are sodium and potassium salts usually found in sports drinks like Gatorade and pediatric formulas like Pedialyte.

But if you faint or feel weak or dizzy every time you stand up (even after a couple of hours) or if you have very little urine output, you should visit your doctor because you may be past the point where ingestion of the proper fluids will help and need medical attention immediately. If you're more dehydrated than you realized, especially if you can't hold fluids down because of vomiting, you may need to receive IV fluids to speed up the rehydration process.

Occasionally, dehydration might be a sign of something more serious, such as diabetes, so your doctor may run tests to rule out any other potential problems.

Preventing Dehydration

To prevent dehydration you simply need to replenish the liquids that are lost throughout the day. By the time you feel thirsty you are already dehydrated—you want to avoid becoming thirsty in the first place. Pay attention to the color of your urine; if it is darker than normal, it could be an indication that you are dehydrated.

Drink lots of fluids, especially on hot, dry, windy days. Water is usually the best choice. It is best to drink fluids before and at regular intervals (every 20 minutes or so) during the course of an activity, and after the activity ends.

Many resources and sites will tell you to drink eight glasses of water a day, or give you a set number of liters to drink, but the honest truth is that everybody is different and only you will know how much your body needs.