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How to Prevent Dehydration

How to Prevent Dehydration

“Dehydration occurs when you use or 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 you don’t replace lost fluids, you will get dehydrated. Anyone may become dehydrated, but the condition is especially dangerous for young children and older adults. The most common cause of dehydration in young children is severe diarrhea and vomiting. Older adults naturally have a lower volume of water in their bodies, and may have conditions or take medications that increase the risk of dehydration.”1

“Water is essential for life. From the time that primeval species ventured from the oceans to live on land, a major key to survival has been prevention of dehydration. The critical adaptations cross an array of species, including man. Without water, humans can survive only for days. Water comprises 75% body weight in infants to 55% in elderly and is essential for cellular homeostasis and life. Nevertheless, there are many unanswered questions about this most essential component of our body and our diet.”2

Tips to Stay Hydrated

There is water inside our cells, vessels and all those spaces between these cells and vessels. Most of our body weight is water.

Our whole body is 75% water (H2O). With normal daily body functions, we lose a considerable amount of it. Most of the time, this goes unnoticed by us, not realizing the importance of staying properly hydrated for our organs and body to work correctly.

“To keep your body hydrated, aim for a fluid intake of about:  3 L (12 cups) for men 19 years old and over each day. 2.2 L (9 cups) for women 19 years old and over each day.”3

“The amount of water you need to drink each day will change. You will need to drink more if it is a hot day, or if you are exercising. Your body will tell you when you are thirsty. Dehydration means your body does not have enough water and being thirsty is often a sign of already being dehydrated.”4

“Fluids include water and other beverages such as milk, juice, broth or soups, coffee, and tea. Water is one of the best fluid choices, but it is a myth that you need 8 cups a day to stay healthy. Fluid helps you stay healthy and energized. It also: controls your body temperature aids digestion carries nutrients around your body cushions organs and joints gets rid of waste keeps your bowels regular Your body loses water by sweating, breathing and getting rid of waste. If you lose more fluid than you take in you can get dehydrated.”5

When do we lose water?

“For sedentary to moderately active individuals under temperate conditions, water is lost from the body via urine, feces, respiration, and evaporation. During increased physical activity and in conditions other than temperate, sweat loss contributes to body water loss. The minimal amount of fluid loss that can occur is referred to as the obligatory water loss. However, a variety of factors can affect obligatory loss. For example, obligatory urine loss occurs because of the need to remove various solutes from the body. The minimum water required for urine is dependent on the daily solute excretory load, primarily determined by diet, and the maximum urinary concentration achievable. Urinary concentrating ability varies with age and with renal disease. Under normal conditions, fecal water loss is quite small, estimated at about 100 mL/day.”6

We lose water with just simple common daily body functions:

  • With Transpiration. After any exercise, a simple walk or only by being able to move.
  • When we have bowel movements, and our body gets rid of the stool to clean our digestive system.
  • When we urinate
  • When we sweat to regulate our body temperature and cool our body, and vice versa
  • When we breathe, and humidified air leaves our body

Consequently, body water levels are always changing. When we lose more water than we take in, dehydration occurs. For this reason, the amount of water we drink must depend on the activities we do. Ideally, 1.5 or 2 liters per day are enough to recover the amount of water that has left our body.

“Humans may drink for various reasons, particularly for hedonic ones but most of drinking is due to water deficiency which triggers the so-called regulatory or physiological thirst. The mechanism of thirst is quite well understood today and the reason non-regulatory drinking is often encountered is related to the large capacity of kidneys to rapidly eliminate excesses of water or reduce urine secretion to temporarily economize on water. But this excretory process can only postpone the necessity for drinking or for stopping drinking an excess of water. Non-regulatory drinking is often confusing, particularly in wealthy societies facing highly palatable drinks or fluids that contain other substances that the drinker seeks. The most common of them are sweeteners or alcohol to which water is served as a vehicle. Drinking these beverages isn’t due to excessive thirst or hyperdipsia as it can be shown by offering pure water instead and finding out that the same drinker is, in fact, hypodipsia (Characterized by abnormally diminished thirst).”7

How to prevent dehydration

“Dehydration may be brought about in two main ways: (A) Insufficient intake of water. (B) Loss of bodily secretions from the alimentary tract or loss of sweat. Insufficient intake of water occurs when water is not available or when it cannot be drunk due to great weakness, unconsciousness or dysphagia from some local cause. Loss of bodily secretions in this country usually results from vomiting, diarrhea, fistula or gastric aspiration. Profuse sweating occurs in 346 tropical climates or under certain industrial conditions; occasionally it arises from mistaken over-heating of patients, especially unconscious patients by blankets or hot air cradles.”8 

“To prevent dehydration, drink plenty of fluids, enough so that your urine is light yellow or almost clear like water. Choose water and other caffeine-free clear liquids until you feel better. Stay away from drinks with alcohol or caffeine. If you do not feel like eating or drinking, try taking small sips of water, sports drinks, or Gatorade.”9

Here are some handy tips that will help you stay hydrated

  • Take more water with you. If you have outdoor activities, are going to practice any sport or are just going to walk outside, always bring extra water to replace the water you will lose.
  • Avoid outdoors exercise or long walks outside when it is too hot. High temperatures will increase the loss of body fluids.
  • Check the weather online or listen to weather forecasts before you make any outdoors plan.
  • Do not force your body. If you’ll be exposed to hot weather, bring enough water with you and take a few minutes to sit down during your walks to cool down, hydrate and keep on without forcing your body.
  • Make sure that elders and children drink enough liquids or water. We all have to help children and older adults and be sure they are drinking plenty of fluids to stay healthy and hydrated. Not only when they are exposed to hot temperatures, but we also have to encourage them to drink every day to assure proper organs and body functions.

Ten tips for drinking more water

  1.  “On a sedentary day, try to drink around two liters of water.
  2.  Start by drinking a glass of fresh water when you get up in the morning.
  3.  If you are not used to drinking water regularly, try initially replacing just one of your other drinks a day with fresh water, increasing your consumption as the weeks go by.
  4. Ask for a glass of tap water to go with your coffee and tea in cafés.
  5. Drink a glass of water before and during each meal.
  6. Hot water with fresh mint, lemon balm or a piece of fruit in – like lime, lemon, orange, etc – often helps those who want a hot drink.
  7. Carry a bottle filled with chilled tap water with you whenever you leave the house.
  8. During exercise, drink at 10 to 15-minute intervals or think of it as a full glass every 30 minutes – drink slowly and drink early, it’s physically easier to do this when you are still feeling fresh.
  9. Keep a check on your urine. As a general guide to hydration, it should be plentiful, pale in color and odorless.
  10. Ask for a jug of iced tap water with your meal when in restaurants and with your alcohol when in bars – good establishments will be happy to provide this.”10

“Many chronic diseases have multifactorial origins. In particular, differences in lifestyle and the impact of the environment are known to be involved and constitute risk factors that are still being evaluated. Water is quantitatively the most important nutrient. There is strong evidence showing that good hydration reduces the risk of urolithiasis. Less strong evidence links good hydration with reduced incidence of constipation, exercise asthma, hypertonic dehydration in the infant, and hyperglycemia in diabetic ketoacidosis. Good hydration is associated with a reduction in urinary tract infections, hypertension, fatal coronary heart disease, venous thromboembolism, and cerebral infarct but all these effects need to be confirmed by clinical trials. For other conditions such as bladder or colon cancer, evidence of a preventive effect of maintaining good hydration is not consistent.”11


(1) Dehydration. Mayo Clinic Staff. Mayo Clinic. 2018.

(2, 7, 11) Water, Hydration and Health. Popkin, B., D’ Anci, K., & Rosemberg, I. Nutrition Reviews. 2010.

(3, 5) Guidelines for Drinking Fluids to Stay Hydrated. Dietitians from Canada. 2014.

(4) Drink Water Instead. Kidney Health Australia. 2017.–kidney-health-australia-fact-sheet.pdf

(6) Water Requirements, Impinging Factors, and Recommended Intakes. Grandjean, A. World Health Organization. 2014.

(8) The Maintenance Of Fluid Balance. Marriot, H. The Royal College Of Surgeons. 1950.

(9) Preventing Dehydration for People with Urinary Diversion. Spilak, D. University Of Michigan, Health System. 2015.

(10) Hydration Best Practice Toolkit for Hospitals and Healthcare. Water UK. Water For Health. 2007.

María Laura Márquez
13 October, 2018

Written by

María Laura Márquez, general doctor graduated from The University of Oriente in 2018, Venezuela. My interests in the world of medicine and science, are focused on surgery and its breakthroughs. Nowadays I practice my more: