give regular small sips of rehydration solution to replace lost fluids — ask your pharmacist to recommend one. do not give young children fruit juice or fizzy drinks — it can make diarrhoea or vomiting worse. Drinking fluids regularly can reduce the risk of dehydration. Water or diluted squash are good choices.

You should drink enough during the day, so your pee is a pale clear colour. Drink more when there's a higher risk of dehydrating. For example, if you're being sick, sweating due to hot weather or exercise, or you have diarrhoea.

Children under the age of 5 should get plenty of fluids to avoid dehydration. Page last reviewed: 14 November Next review due: 14 November Home Health A to Z Back to Health A to Z. Important Babies, children and older adults are more at risk of dehydration. Find a pharmacy. Urgent advice: Ask for an urgent GP appointment or get help from NHS if:.

As we age, drinking enough water is even more important. Older adults are also more likely to take diuretics and other medications that cause fluid loss in the body. Adding just a few glasses of water to your daily intake can have a positive effect on cognition , stabilize your emotions, and even combat feelings of anxiety.

This is especially important for older adults who are at higher risk for both dehydration and impaired cognitive function. Your body needs water in order to digest food properly. Without enough, you may experience irregular bowel movements, gas, bloating, heartburn, and other discomforts that can hurt your quality of life.

When you make it a point to stay hydrated, it can help get things moving in the right direction again. Water aids in breaking down soluble fiber from your diet to keep your digestion process on track.

Mineral water is especially beneficial—look for products enriched with sodium and magnesium. Dehydration can slow down circulation and affect the flow of oxygen to your brain. A lack of fluids can also cause your heart to work harder to pump oxygen all throughout your body.

All of that expended energy can make you feel tired, sluggish, and less focused. Since it provides a sense of fullness, water can help you feel satisfied in between meals—instead of heading to the snack cupboard.

It can also help boost your metabolism. Consider this:. Staying hydrated helps your joints stay well-lubricated, which helps reduce friction by creating more of a "cushion" between the bones.

Less friction means smoother-moving joints and fewer aches and pains. Research shows that when you're dehydrated, your body stores more heat.

This in turn lowers your ability to tolerate hot temperatures. Hydrating with plenty of water helps you produce sweat when you're overheated during activity, which in turn cools your body down.

This built-in cooling mechanism is critical in preventing heat stroke and other potentially deadly heat-related conditions. Kidney stones are clumps of mineral crystals that form in the urinary tract. If you've ever experienced one, you know how painful they can be.

Staying hydrated with plenty of water can help dilute the concentration of minerals in your urinary tract and make stones less likely. Water also helps flush harmful bacteria from your bladder and can aid in preventing urinary tract infections UTIs.

Your blood is made up largely of H2O. When you don't drink enough glasses of water, it becomes concentrated, which can cause an imbalance of vital minerals electrolytes. These minerals, like potassium and sodium, are key to the proper functioning of your heart. Hydrating with plenty of water supports your own powerful, built-in detox processes and can help enhance your overall health.

Even a mild fluid loss can cause the brain to contract away from the skull, leading to headaches and migraines in some people. Staying hydrated may help keep head pain in check. Here are some tips:. Mild dehydration can usually be resolved by drinking fluids, but severe dehydration can be life-threatening.

Seek medical help immediately if you experience some or all of the symptoms below:. Your doctor can help you come up with a hydration plan that meets your personal health needs and lifestyle.

National Library of Medicine. Adult Dehydration. Vinu A. Vij et. Journal of Clinical and Diagnostic Research. Guillermo Bracamontes-Castelo et.

Effect of water consumption on weight loss: a systematic review. Nutrición Hospitalaria. An et. Plain water consumption in relation to energy intake and diet quality among U.

adults, — Nutritional Epidemiology. Get information on prevention and how to manage ongoing health conditions focused on physical and mental health.

You lose water when you sweat. If you do vigorous activity and don't replace fluids as you go along, you can become dehydrated. Hot, humid weather increases the amount you sweat and the amount of fluid you lose.

Increased urination. This may be due to undiagnosed or uncontrolled diabetes. Certain medications, such as diuretics and some blood pressure medications, also can lead to dehydration, generally because they cause you to urinate more.

Anyone can become dehydrated, but certain people are at greater risk: Infants and children. The most likely group to experience severe diarrhea and vomiting, infants and children are especially vulnerable to dehydration.

Having a higher surface area to volume area, they also lose a higher proportion of their fluids from a high fever or burns. Young children often can't tell you that they're thirsty, nor can they get a drink for themselves. Older adults.

As you age, your body's fluid reserve becomes smaller, your ability to conserve water is reduced and your thirst sense becomes less acute. These problems are compounded by chronic illnesses such as diabetes and dementia, and by the use of certain medications. Older adults also may have mobility problems that limit their ability to obtain water for themselves.

People with chronic illnesses. Having uncontrolled or untreated diabetes puts you at high risk of dehydration. Kidney disease also increases your risk, as do medications that increase urination.

Even having a cold or sore throat makes you more susceptible to dehydration because you're less likely to feel like eating or drinking when you're sick. People who work or exercise outside.

When it's hot and humid, your risk of dehydration and heat illness increases. That's because when the air is humid, sweat can't evaporate and cool you as quickly as it normally does, and this can lead to an increased body temperature and the need for more fluids.

Dehydration can lead to serious complications, including: Heat injury. If you don't drink enough fluids when you're exercising vigorously and perspiring heavily, you may end up with a heat injury, ranging in severity from mild heat cramps to heat exhaustion or potentially life-threatening heatstroke.

Urinary and kidney problems. Prolonged or repeated bouts of dehydration can cause urinary tract infections, kidney stones and even kidney failure. Electrolytes — such as potassium and sodium — help carry electrical signals from cell to cell.

If your electrolytes are out of balance, the normal electrical messages can become mixed up, which can lead to involuntary muscle contractions and sometimes to a loss of consciousness. Low blood volume shock hypovolemic shock. This is one of the most serious, and sometimes life-threatening, complications of dehydration.

It occurs when low blood volume causes a drop in blood pressure and a drop in the amount of oxygen in your body.

People may need to take in more fluids if they are experiencing conditions such as: Vomiting or diarrhea. If your child is vomiting or has diarrhea, start giving extra water or an oral rehydration solution at the first signs of illness. Don't wait until dehydration occurs.

Strenuous exercise. In general, it's best to start hydrating the day before strenuous exercise. Producing lots of clear, dilute urine is a good indication that you're well-hydrated.

During the activity, replenish fluids at regular intervals and continue drinking water or other fluids after you're finished. Hot or cold weather. You need to drink additional water in hot or humid weather to help lower your body temperature and to replace what you lose through sweating. You may also need extra water in cold weather to combat moisture loss from dry air, particularly at higher altitudes Illness.

Older adults most commonly become dehydrated during minor illnesses — such as influenza, bronchitis or bladder infections. Make sure to drink extra fluids when you're not feeling well. By Mayo Clinic Staff. Oct 14, Show References. Marx JA, et al. Infectious diarrheal disease and dehydration. In: Rosen's Emergency Medicine: Concepts and Clinical Practice.

Philadelphia, Pa. Accessed Aug. Aurbach PS. Dehydration, rehydration and hyperhydration. In: Wilderness Medicine. National Institute of Diabetes and Digestive and Kidney Diseases.

Rochester, Minn. Somers MJ. Clinical assessment of hypovolemia dehydration in children. Miller HJ. Dehydration in the older adult. Journal of Gerontological Nursing. Heat and athletes. Centers for Disease Control and Prevention. Treatment of hypovolemia dehydration in children.

Sterns RH. Etiology, clinical manifestations and diagnosis of volume depletion in adults. Heat-related emergencies. Freedman S. Oral rehydration therapy. Thomas DT, et al. American College of Sports Medicine Joint Position Statement. Nutrition and Athletic Performance. Medicine and Science in Sports and Exercise.

Takahashi PY expert opinion. Brain cells are particularly susceptible to more severe levels of dehydration. Consequently, confusion is one of the best indicators that dehydration has become severe.

Very severe dehydration can lead to coma and death. Older people are particularly susceptible to dehydration. In older people, common causes of dehydration include. Disorders that make obtaining fluids difficult usually because of restricted mobility, such as after a stroke Overview of Stroke A stroke occurs when an artery to the brain becomes blocked or ruptures, resulting in death of an area of brain tissue due to loss of its blood supply cerebral infarction.

Symptoms occur suddenly Additionally, older people sense thirst more slowly and less intensely than younger people do, so even those who are otherwise well may not drink enough fluids for a variety of reasons, including incontinence Urinary Incontinence in Adults Urinary incontinence is involuntary loss of urine.

read more or the fear of incontinence. Older people have a higher percentage of body fat. Because fat tissue contains less water than lean tissue, the total amount of water in the body tends to decrease with age.

In overhydration Overhydration Overhydration is an excess of water in the body. read more , the body contains too much water. In older people, the kidneys excrete excess water less efficiently, and thus older people can develop overhydration more easily than younger people do.

Swelling edema may or may not occur. Dehydration can often be diagnosed from symptoms and the results of a doctor's examination. But sometimes doctors do blood tests for people who appear seriously ill or who take certain drugs or have certain disorders.

For people who require more monitoring or testing in an emergency department or intensive care unit, doctors sometimes use ultrasound or special catheters to measure the severity of dehydration.

Dehydration normally causes the sodium level in the blood to increase. The reason is that although the common causes of dehydration such as profuse sweating Excessive Sweating People with excessive sweating hyperhidrosis sweat profusely, and some sweat almost constantly.

Excessive sweating usually has no clear cause but is sometimes caused by infections, metabolic read more , vomiting Nausea and Vomiting in Adults Nausea is an unpleasant feeling of needing to vomit. read more , and diarrhea Diarrhea in Adults Diarrhea is an increase in the volume, wateriness, or frequency of bowel movements.

read more result in a loss of electrolytes Overview of Electrolytes More than half of a person's body weight is water. Doctors think about water in the body as being restricted to various spaces, called fluid compartments.

The three main compartments are Fluid read more especially sodium and potassium , even more water is lost, so sodium becomes more concentrated in the blood. Prevention of dehydration is better than cure. Adults should drink at least 6 glasses of fluids daily including fluid from eating foods high in water content, such as fruits and vegetables.

Flavored sports drinks have been formulated to replace electrolytes lost during vigorous exercise. These drinks can be used to prevent dehydration. People should drink fluids with electrolytes before and during vigorous exercise as well as afterward.

Before exercising, people with heart or kidney disorders should consult their doctors about how to safely replace fluids. People should make sure that older family members have access to plenty of water when they are alone in a hot building or place.

For treating mild dehydration, drinking plenty of water may be all that is needed. With moderate and severe dehydration, lost electrolytes especially sodium and potassium must also be replaced.

read more that contain appropriate amounts of electrolytes are available without a prescription. These solutions work well to treat dehydration, especially that caused by vomiting or diarrhea in children. Sports drinks do not necessarily contain enough electrolytes to be an adequate substitute for these solutions.

People who are vomiting may not be able to hold down enough fluid to treat dehydration. More severe dehydration requires treatment by doctors with intravenous solutions containing sodium chloride salt. The intravenous solution is given rapidly at first and then more slowly as the physical condition improves.

Treatment is also directed at the cause of dehydration. For example, when people have nausea and vomiting Nausea and Vomiting in Adults Nausea is an unpleasant feeling of needing to vomit.

read more or diarrhea Diarrhea in Adults Diarrhea is an increase in the volume, wateriness, or frequency of bowel movements. read more , drugs to control or stop the vomiting or diarrhea may be used. Learn more about the Merck Manuals and our commitment to Global Medical Knowledge.

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