Your body regularly loses water through sweating and urination. If you don’t replace it quickly enough, you get dehydrated. People at risk include athletes, those who work in the heat, older adults, and those with chronic conditions.
Dehydration occurs when your body loses more fluid than you drink. Common causes include:
excessive sweating
vomiting
diarrhea
Experts recommend women drink 2.7 liters (92 fluid ounces or 11.5 cups) per day and men drink 3.7 liters (124 fluid ounces or 15.5 cups) daily. Highly active people and those exposed to high temperatures should increase their water intake to avoid dehydration.
When your body loses too much water, its organs, cells, and tissues fail to function as they should, which can lead to dangerous complications, such as shock.
Dehydration can be mild or severe. You can usually treat mild dehydration on your own. Severe dehydration requires treatment in a hospital or emergency care setting.
Athletes exposed to direct sun aren’t the only ones at risk of dehydration. Bodybuilders and swimmers are also among the athletes who commonly develop the condition.
Strange as it may seem, it’s possible to sweat in water. Swimmers lose a lot of sweat when swimming.
Any situation or condition that causes your body to lose more water than usual leads to dehydration.
Sweating
Sweating is part of your body’s natural cooling process, accounting for about 22% of its heat loss. When you become hot, your sweat glands activate to release moisture from your body through evaporation in an attempt to cool it off.
As a drop of sweat evaporates from your skin, it takes a small amount of heat with it. The more sweat you produce, the more evaporation there is, and the more you’re cooled off. Sweating also hydrates your skin and maintains the balance of electrolytes in your body.
The fluid you sweat comprises mainly salt and water. Excessive sweating can cause dehydration since you lose a large amount of water. The technical term for excessive sweating is hyperhidrosis.
Illness
Illnesses that cause continuous vomiting or diarrhea can result in dehydration. This is because vomiting and diarrhea can cause you to expel too much water.
Vomiting and diarrhea can also cause you to lose essential electrolytes, minerals your body uses to control muscles, blood chemistry, and organ processes. These electrolytes are found in blood, urine, and other bodily fluids.
Vomiting or diarrhea can impair these functions and cause severe complications.
Fever
If you have a fever, your body loses fluid through your skin’s surface in an attempt to lower your temperature. Often, fever can cause you to sweat so much that if you don’t drink to replenish, you could end up dehydrated.
Urination
Urination is your body’s regular way of releasing toxins. Some conditions, like diabetes, can cause chemical imbalances, which can increase your urine output. If you don’t replace the fluid lost through excessive urination, you risk developing dehydration.
Before beginning any tests, a doctor will review any symptoms you have to rule out other conditions. After taking your medical history, your doctor will check your vital signs, including your heart rate and blood pressure. Low blood pressure and rapid heart rate can indicate dehydration.
Your doctor may use a blood test to check your electrolyte levels, which can help indicate fluid loss. A blood test can also check your creatinine levels. This helps your doctor determine how well your kidneys are functioning, an indicator of the degree of dehydration.
A urinalysis is an exam that uses a urine sample to check for the presence of bacteria and electrolyte loss. The color of your urine can also indicate dehydration when combined with other symptoms. Dark urine alone can’t diagnose dehydration.
Treatments for dehydration include rehydrating methods, electrolyte replacement, and treating diarrhea or vomiting if needed.
Rehydration
The quickest remedy to mild dehydration is drinking to replenish the lost water and electrolytes. In addition to water, you may consider drinking an electrolyte-containing rehydration drink, such as a low-sugar sports or electrolyte drink or an oral rehydration solution.
Experts often recommend Pedialyte as an oral rehydration solution for children with dehydration.
Rehydration by drinking may not be possible for all people, like those who have severe diarrhea or vomiting. In this case, healthcare professionals can administer fluids intravenously.
To do this, they insert a small IV tube in a vein in your arm or hand. It provides a solution that’s often a mix of water and electrolytes.
Homemade rehydration solution
If an electrolyte drink isn’t available, you can make your own rehydration solution using:
1/2 teaspoon salt
6 teaspoons sugar
1 liter water
Be absolutely certain that you’re using an accurate measurement. Using too much salt or sugar can be dangerous.
What to avoid when dehydrated
Avoid soda, alcohol, overly sweet drinks, or caffeine. These drinks can worsen dehydration.
If you’re ill, increase your fluid intake, especially if you’re vomiting or having diarrhea. If you can’t keep down liquids, seek medical attention.
If you’re going to exercise or play sports, drink water before the activity. Replace your fluids at regular intervals during the workout, and make sure to drink water or electrolytes after.
Dehydration occurs when you’re not getting enough fluids. Whether from exercise, hot weather, or an illness, dehydration can quickly become dangerous — no matter the cause.
You can help prevent dehydration by drinking plenty of water throughout the day and taking electrolytes if you start noticing early symptoms of fluid loss.
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