Dehydration can be defined as "the excessive loss of water from the body." Diseases of the gastrointestinal tract can lead to dehydration in various ways. Often, dehydration becomes the major problem in an otherwise self-limited illness. Fluid loss may even be severe enough to become life-threatening.

Dehydration occurs when you lose more fluid than you take in and your body doesn't have enough water and other fluids to carry out its normal functions. If lost fluid remains unreplenished, you may suffer serious consequences.

Causes of Dehydration

One common cause of dehydration in teens is gastrointestinal illness. When you're flattened by a stomach bug, you lose fluid through vomiting and diarrhea.

Excessive loss of fluid through the intestinal tract can happen when the intestine is "inflamed" or damaged, or when bacteria or viruses cause the lining of the intestine to produce more fluid than can be absorbed.

Dieting can sap a person's water reserves as well. Beware of diets or supplements, including laxatives and diuretics that emphasize shedding "water weight" as a quick way to lose weight. Losing water weight is not the same thing as losing actual fat.

Water is essential to human life: It forms the basis for all body fluids, including blood and digestive juices; it aids in the transportation and absorption of nutrients; and it helps eliminate waste.

Fever In general, the higher your fever, the more dehydrated you may become. If you have a fever in addition to diarrhea and vomiting, you lose even more fluids.

Natural Home Remedies for Dehydration

Bland foods. If you've experienced dehydration, stick to foods that are easily digested for the next 24 hours, because stomach cramps are a symptom of dehydration and can recur. Try soda crackers, rice, bananas, potatoes, and flavored gelatins. Gelatins are especially good since they are primarily made of water.

Drink more with exercise. When you exercise, be sure that you drink plenty of water before, during, and after. An hour before you exercise, drink 8 to 16 ounces of water, unsweetened juice, or a sports drink, says Dr. Besdine. If you exercise enough that you’re breaking a sweat, you need about 20 to 40 ounces of water per hour, which is 4 to 8 ounces every 15 minutes.

Lime juice. Add 1 teaspoon lime juice, a pinch of salt, and 1 teaspoon sugar to a pint of water. Sip the beverage throughout the day to cure mild dehydration.

Stay cool. Hot weather is another common cause of dehydration in the elderly, says Dr. Besdine. Water loss increases in a warm environment, he says. Always use an air conditioner or fans in hot weather, Dr. Besdine advises. “Older adults should never stay in temperatures over 100°F, especially if they are indoors without adequate circulating air.”

Vinegar. Since achy muscles are a side effect of dehydration, this can bring relief. Add 8 ounces apple cider vinegar to a bathtub of warm water. Soak in tub for at least 15 minutes.

Add a light protein. "When you're feeling a little better, you can move on to a light protein like chicken breast or fish," Dr. Koch says. Chicken noodle or chicken with rice soup is perfect for this, he says. Be sure to skim off as much fat from the soup as you can.

Apply heat to the abdomen to help relieve pain, cramps, and tenderness. Electric heating pads, moist heat wraps, and water bottles can all be used as needed.

If the dehydration is because of diarrhea or vomiting, give your baby an electrolyte solution. The frequency should be every half-hour to an hour, after the baby has stopped vomiting.