Are You at Risk for Dehydration?

by Carmen Roberts, M.S., R.D., L.D.N. Health Professional, Medical Reviewer

The human body is 60-75 percent water. Each day, you lose water from your body, primarily through urine and sweat. Without replacing the water you need, it’s easy to become dehydrated. There are many different opinions on how much water we should be drinking each day. Here HealthCentral reviews how much is enough to prevent dehydration, and what are the best ways to stay hydrated:

Why is hydration so important?

Water is crucial to many of your body’s functions. Your body loses water each time you exhale, sweat, and use the bathroom. Without enough water, you can become dehydrated. It is important to replace this lost fluid each day with an adequate amount of water to maintain these bodily functions.

"Dehydration is a serious health risk and is one of the primary reasons older Americans are hospitalized each year."

How do you become dehydrated?

The most common causes of dehydration are vomiting, diarrhea, and sweating. Prolonged fever and heat exposure can also cause excessive fluid losses. People most at risk for dehydration are athletes, people living at higher altitudes, and the elderly. If you are living with a chronic condition such as diabetes, you may be at an increased risk, since high blood sugar levels cause increased urination and fluid loss. If you experience frequent urination (caused by uncontrolled diabetes, alcohol intake, and medications such as diuretics, antihistamines, or blood pressure medication), you are also at risk for dehydration.

There are other situations that require increased fluid needs. During pregnancy, extra fluid is needed to help maintain the mother’s increased blood volume. Once the baby is born, sufficient water intake is necessary for breast milk production. Your physician may also advise you to increase your fluid intake if you have a bladder infection or kidney stones, or if you’ve experienced an illness that has caused a prolonged fever, vomiting, or diarrhea.

What are the symptoms of dehydration?

Symptoms of dehydration include dry mouth, fatigue, muscle weakness, headache, and dizziness. Symptoms of severe dehydration include sunken eyes, dry or shriveled skin, low blood pressure, lack of perspiration, increased heart rate, and delirium or even unconsciousness.

A good rule of thumb to see if you are getting enough water is to look at the color of your urine. If it is clear or straw-colored, you are likely getting enough water. If your urine is dark, it is a sign that you are dehydrated. Don’t wait until you are thirsty to drink water — this is typically a sign that you are already dehydrated.

How do you quickly cure dehydration?

If you are dehydrated, start by sipping small amounts of water. You can also try a hydration drink (which contains sodium and potassium — the electrolytes that are lost through sweat). Suck on ice chips or popsicles made from juices or sports drinks to replace lost fluid.

How do you prevent chronic dehydration?

The National Academies of Science, Engineering, and Medicine recommends 91 ounces (11 eight-ounce cups) of fluid each day for women and 125 ounces (16 eight-ounce cups) for men each day. While some of this necessary fluid comes from the foods you eat, most of this needs to come from drinking water. A general guideline is to drink at least half of your body weight in fluid ounces daily. So if you weigh 160 pounds, you need a minimum of 80 ounces (or 10 eight-ounce glasses) of water each day. If you are active and/or live in a warmer climate, your fluid needs may be closer to your total body weight in fluid ounces (for a 160-pound person, this means 160 ounces, or 20 eight-ounce glasses, per day). The average person does not meet their daily fluid needs.

To ensure that you are getting enough water throughout the day, carry a water bottle around with you wherever you go (in the car, at your desk at work, when you are waiting at the doctor’s office, etc.). Sipping on water throughout the day is the easiest way to make sure you’re getting enough fluid. Don’t wait to consume all of your water at once — you will likely feel too full to get in all of your required water for the day.

Do you need more fluid when you exercise?

Proper hydration is critical for athletic performance, particularly when you are exercising in the heat or for long periods of time. When your body is dehydrated, you may experience muscle cramps and fatigue. Without adequate water, your body can’t sweat to cool itself down. This can ultimately lead to heat stroke. When you are exercising outside in the summer, you will need even more water to stay hydrated. For each pound of fluid lost after exercise, you need two to three cups of water to replace that lost fluid.

The bottom line

Dehydration is a serious health risk and is one of the primary reasons older Americans are hospitalized each year. Talk with your healthcare provider if you have concerns about hydration or if you are having difficulty meeting your daily fluid needs.

Carmen Roberts, M.S., R.D., L.D.N.
Meet Our Writer
Carmen Roberts, M.S., R.D., L.D.N.

Carmen is a Registered Dietitian. In addition to writing for HealthCentral, she has spent her career working at Johns Hopkins and is also an adjunct faculty instructor for Excelsior College. Carmen has over 20 years of experience in nutritional counseling, education, writing, and program management and is a certified specialist in adult weight management. She enjoys educating her students and clients about how nutrition affects the body and its role in overall health and wellness.