What Happens to Your Body When You’re Dehydrated

woman drinking glass of water

Story at-a-glance -

  • Dehydration happens when you’ve lost too much water in your body without replacing it, which prevents your body to perform its normal functions
  • Infants and children are especially prone to dehydration since their bodies are composed of 70 percent and 65 percent water, respectively
  • Beverage companies claim that sports drinks will help replenish the electrolytes in your body during exercise or outdoor activities, but the truth is the ingredients of your favorite sports drinks will not hydrate and benefit you, and may even be detrimental to your health
  • When you nourish your body with structured water, you are restoring your body to a balanced and whole state

Dehydration is no ordinary health issue. Anyone can become dehydrated for various reasons, so it is important that you always hydrate yourself with filtered water. Read on to learn more about symptoms of dehydration and how you can prevent it.

What Is Dehydration?

Water makes up nearly two-thirds of the human body. It plays a large part in many bodily functions, such as lubricating your joints and eyes, keeping your skin healthy by eliminating toxins and facilitating proper digestion.1 Once your body loses water, it needs to be replaced to maintain balance between the salts, glucose and other minerals in your system that keep your biological processes working optimally.2

When your body becomes dehydrated, drastic changes can immediately occur. Research has shown that dehydration decreases brain tissue fluid, which can result in changes in brain volume.3 Your blood becomes thicker as well, straining your cardiovascular system by making your heart work harder. To make matters worse, dehydration compromises your body’s ability to regulate its temperature.4

Losing just 1 to 2 percent of your entire water content can cause thirstiness, a sign that you need to replenish the lost liquids.5 Dehydration happens when you've lost too much water without replacing it, preventing your body from performing its normal functions.6 Mild dehydration can easily be treated but if it reaches extreme levels, it can be life-threatening and will require immediate medical attention.

Signs and Symptoms of Dehydration

Here are the mild and severe symptoms of dehydration:7

Mild to Moderate Dehydration Severe Dehydration
Dry, sticky mouth Extreme thirst
Sleepiness or tiredness Irritability and confusion
Dry skin Sunken eyes
Headache Dry skin that doesn't bounce back when you pinch it
Constipation Low blood pressure
Dizziness or lightheadedness Rapid heartbeat
Few or no tears when crying Rapid breathing
Minimal urine No tears when crying
Dry, cool skin8 Fever
Muscle cramps Little or no urination, and any urine color that is darker than usual
In serious cases, delirium or unconsciousness

Infants and children are more vulnerable to dehydration, so immediate attention must be given to them if you see these symptoms:9

Mild to Moderate Dehydration Severe Dehydration
Urinates less frequently (for infants, fewer than six wet diapers per day) Very fussy
Plays less than usual Excessively sleepy
Parched, dry mouth Sunken eyes
Fewer tears when crying Cool, discolored hands and feet
Sunken soft spot on the head (fontanelle) Wrinkled skin
Loose stools (if dehydration is caused by diarrhea). If dehydration is due to fluid loss, there will be less frequent bowel movements Urinates only once or twice a day

Chronic dehydration can affect your organs and lead to kidney stones,10 constipation11 and electrolyte imbalances that may result in seizures.12

Whether it is mild, moderate or severe dehydration, the liquids lost from your body must be immediately replaced. If any of the aforementioned symptoms appear, get professional treatment as soon as possible.

What Causes Dehydration?

There are various reasons why dehydration occurs, and the causes can be a result of both losing too many fluids and not taking in enough. For example, intense physical activity can cause you to sweat profusely and lose substantial amounts of water, so proper hydration is necessary to replenish what you’ve lost. Other causes of dehydration include:13

  • Diarrhea — This condition prevents your intestinal tract from absorbing water from the foods that you eat, making it the most common cause of dehydration.
  • Vomiting — Common causes include foodborne illnesses, nausea and alcohol poisoning.
  • Sweating — Vigorous sweating may occur for various reasons like fever and engaging in intense physical activity. Profuse sweating can also occur when you are working in a hot environment.14
  • Diabetes — Aside from having high blood sugar levels, diabetics may be taking medications that can cause frequent urination.
  • Frequent urination — Nondiabetics may urinate frequently because of alcohol intake and certain drugs like antihistamines, blood pressure medications and antipsychotics.

Who Is at Risk of Dehydration?

Everyone is prone to dehydration, but some people have a higher risk for it, such as those who engage in strenuous exercise. One example is mountain climbing. It is especially hard for hikers to stay hydrated because the pressure at high altitudes makes them sweat more and breathe harder.15

Professional athletes, particularly those who compete in marathons, triathlons and cycling tournaments, are also predisposed to dehydration. Research suggests that even low levels of dehydration can impair their cardiovascular and thermoregulatory response.16

One study17 even revealed that dehydration can affect basketball players' performance. The study focused on 17 males ranging from 17 to 28 years old, and determined their performance based on different dehydration levels of up to 4 percent. The result showed that when there's an increase in dehydration, skill performance decreases.

Infants are especially prone to dehydration since their bodies are composed of 78 percent water.18 Since their bodies are more vulnerable to water depletion, their need for water is greater than adults.

Elderly people are also at risk for dehydration since the thirst mechanism weakens as a person grows older. According to BBC News,19 1 in 5 seniors is not getting enough water every day, with several causes for that, ranging from forgetfulness to a desire to fight incontinence by consuming fewer fluids, to simply being too frail to care for their personal needs. Those with dementia were found to have a sixfold increased risk for dehydration.

Those who have chronic diseases that cause frequent urination such as diabetes or kidney problems have an increased risk of dehydration.20 If you have a chronic illness that causes dehydration, make sure to take the necessary steps to protect your health.

How to Prevent Dehydration

Since dehydration can be life-threatening, it is important that you replenish your body with water immediately. Water plays such an immense role in your bodily functions, making it an essential part of your everyday life.

Always bring a bottle of water with you during exercise or any physical activity, especially when the temperature's too hot. One good rule of thumb to prevent dehydration is to drink as much water as it takes for your urine to turn light yellow. Dark urine means that your kidneys are retaining liquids in an effort to have enough for your body to perform its normal functions.

It is especially important to pay attention if you are sick with fever, are vomiting or have diarrhea, so you don’t become dehydrated. Be sure to drink lots of water to replace the liquids that you’ve lost. If you are vomiting or have diarrhea to the point that you cannot drink enough to stay hydrated, you may need to visit an emergency department for help in maintaining hydration.

Sports Drinks Will Not Keep You Hydrated

Sports drinks are one of the most commercialized beverages today — from TV advertisements to popular athlete endorsers, mainstream media make it look like drinking them will keep you healthy and well-hydrated.

Beverage companies advertise that sports drinks will help replenish the electrolytes in your body during exercise or outdoor activities, but the truth is the drinks with actual science studies behind them were created for high-performance athletes who deplete their water stores quickly, not for the average person looking to address thirst issues. Indeed, downing too many of these drinks may even be detrimental to your health.21

A typical sports or energy drink contains high amounts of citric acid. According to a news report from NPR, drinking sports or energy drinks that have citric acid can chip away the enamel in your teeth faster. What’s more, the precise amount of citric acid is not disclosed on the product labels.22

Aside from sports drinks, there are other sweetened beverages that won’t give you any benefit, like sodas. These are equally unhealthy for you, as a 20-ounce bottle of cola gives you 16 teaspoons of sugar, usually in the form of high-fructose corn syrup.23

Commercial fruit juices are another group of sweetened drinks that have too many sugars and not enough value to make them useful for hydrating purposes. For example, Minute Maid's 100% Apple Juice contains 49 grams of sugar in a 15.2-ounce bottle.24

Most processed fruit juices bear little resemblance to what an actual fresh fruit juice would be. Commercial fruit juices are pasteurized and their oxygen is removed to preserve them for a long time, making the juices less nutrient-dense. Store-bought fruit juices with an expiration date of 60 days or more is a sign that they are heavily processed, so it’s advisable to stick with water when you’re thirsty.

Choose to Drink Living Water

If you’re on a community water system, don’t just turn on the tap and fill a glass or water bottle, as it may very well contain fluoride, as well as heavy metals and disinfection byproducts that can have ill effects on your health. Installing a water filter in your home, both at the tap and preferably also at the point of entrance, can ensure that these harmful contaminants are removed.

If you want the best water for you and your family, I suggest drinking structured or "living" water, such as deep spring water. According to Gerald Pollack, one of the world's leading research scientists on the physics of water, structured water or EZ "exclusion zone" water is the same type of water found in your body’s cells. It has a negative charge, and works just like a battery by holding and delivering energy.

Since distilled water is too acidic and alkaline water is too alkaline, you should nourish your body only with structured water, as it contains the ideal PH range of 6.5 to 7.5, which enables your body to maintain a balanced and whole state.

I personally drink vortexed water since I became a fan of Viktor Schauberger, who did so much work regarding vortexing many years ago.25 By creating a vortex in your glass of water, you are putting energy into it and increasing EZ as well.

Ideal EZ water can be found in glacial melt, but since it is practically inaccessible for almost everyone, natural deep spring water is a good source. When storing water, use glass jugs and avoid plastic bottles since they contain bisphenol A, bisphenol B and phthalates, which are harmful to your health.26,27

Other Natural Thirst-Quenchers for Preventing Dehydration

If you want to drink something more flavorful than water, you can opt for raw, organic green juice made from fresh vegetables. However, I recommend refraining from drinking juice with too many fruits as it will have high amounts of sugar and calories. Go for a green juice recipe that combines one or two fruits only and larger amounts of greens like spinach, celery or kale. That way, you can minimize your sugar intake and still get all the nutrients from the fruits and vegetables in their purest forms.

I advise keeping your fructose consumption below 25 grams per day. If you have Type 2 diabetes, insulin resistance or heart disease, it is wise to minimize your total fructose to 15 grams daily.

Coconut water also serves as a great replacement for sports drinks. It provides optimal health benefits due to its anti-inflammatory28 and antioxidant29 effects. A word of caution: Coconut water also contains sugar, so drink it in moderation, preferably after a cardio workout, when you need to replace minerals and fluids.

The Key to Avoiding Dehydration: Listen to Your Body

No one but you can determine if you are hydrated enough. If you feel thirsty or you’re sweating profusely, this is a signal that you need to replenish your body with water immediately. Don’t wait for severe dehydration symptoms to occur before you take action, since this can be life-threatening.

Since anyone can become dehydrated even without any physical activity, keeping a bottle of filtered water nearby can help keep you hydrated. Remember that a healthy person urinates seven to eight times each day, so if you're not urinating frequently it means that you're not drinking enough water.

Remember: Nothing feels more refreshing than cold water to replace the liquids that you've lost. It’s also important to always listen to your body. Once you feel that urge to drink, opt for structured or filtered water rather than artificially sweetened beverages, which can have negative effects on your health.