How Do I Know if I Am Hydrated?


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Taking in a sufficient amount of water is important for a number of reasons—it regulates body temperature, maintains optimal organ function, delivers cells essential nutrients, aids digestion, keeps you feeling full, and even improves your cognitive abilities. Essentially, hydration plays a vital role in almost all of your bodily functions.

Because the average body is around 60% water, you regularly tap into these stores throughout the day. Without replacing the lost water content, you can become dehydrated, with a loss of even 1 to 2% risking cognitive performance impairments and impacting memory skills not to mention the more obvious symptoms of a dry mouth, thirst, constipation, dizziness, and fatigue.

While most people understand the need for proper hydration, what is less acknowledged is the role of electrolytes, such as sodium, potassium, and chloride, play in the body. They help regulate bodily functions and nutrient absorption while maintaining body temperature.

"Your body loses water and electrolytes in a number of ways, including sweat, breathing, and urination, so it’s crucial to replenish as needed," says Vishal Patel, RNS, a fitness nutrition specialist and director of product development at hydration company Nuun.

Here is what you need to know about hydration including why it is important, how much water you need daily, and how to track your hydration levels.

Why Hydration Is Important

Staying hydrated is essential to good health. Not only does proper hydration keep your body regulated, but it also keeps joints lubricated and helps deliver nutrients to your cells. Adequate hydration also helps you sleep better, improves mood, helps fight infections, and can even improve cognition.

In fact, your brain is more than 70% water, so being dehydrated can impact concentration, memory, and alertness. A study of men in their 20s showed that dehydration slowed some brain functions. Participants in the study tended to make more mistakes on vision and memory tests when they were dehydrated.

And another study found that even slight dehydration can cause driving mistakes like drifting into other lanes or having slower reaction times. In fact, driving while dehydrated can worsen driving skills as much as if you were driving intoxicated or while sleep-deprived.

Being dehydrated also can impact blood pressure and cause constipation. It can even make you more sensitive to pain, increase headaches, and affect mood. One study found that women who were only 1.36% dehydrated experienced headaches, while another study found that being dehydrated triggered feelings of anxiety, depression, and tenseness.

If you are dehydrated, it is important to take steps to remedy the situation. Get immediate medical attention if you experience serious signs of dehydration like confusion, rapid pulse, dizziness, fainting, slurred speech, fever, muscle twitching, or an altered mental state.

Signs of Dehydration

Here are some signs of dehydration. If you or a loved one experiences these symptoms, contact a healthcare provider right away.

  • Headache
  • Confusion
  • Tiredness or fatigue
  • Dizziness
  • Light-headedness
  • Dry mouth
  • Extreme thirst
  • Rapid pulse but low blood pressure
  • Loss of appetite or nausea
  • Flushed or red skin
  • Swollen feet
  • Muscle cramps
  • Heat intolerance or chills
  • Constipation
  • Dark-colored urine

Daily Water Intake

There is no one universal approach to how much water an individual should drink. Factors such as gender, age, activity level, medications, and even pregnancy will alter the quantity of adequate water intake required each day.

"Typically, consuming half of your weight in ounces will establish a baseline," says Patel. As an example, a 150-pound person should consume 75 fluid ounces per day (around 2.2 liters).

However, an athlete partaking in daily strenuous training will require a higher water consumption to remain sufficiently hydrated throughout the day. For endurance athletes, the general recommendation is to fully restore water levels within 2 hours of exercise.

Vishal Patel, Fitness Nutrition Specialist

Typically, consuming half of your weight in ounces will establish a baseline.

— Vishal Patel, Fitness Nutrition Specialist

"Depending on your exercise habits, you can adjust environmental conditions," says Patel. "And if you’re exercising regularly, be sure to consume an electrolyte-rich beverage after the workout to replenish stores that may be lost due to sweating."

Remember, too, water is not the only way your body stays hydrated throughout the day. While certain drinks will help you stay hydrated, the food on your plate that contains a higher water content like cucumbers, watermelon, and strawberries also can help add to your daily intake.

How to Measure Your Hydration Levels

Monitoring your hydration levels is simpler than you might think. Typically, it involves paying attention to your body and watching for clues that you need to hydrate. Here are two easy ways to monitor your hydration level.

Monitor Bathroom Habits

Tracking the color of your urine as well as how often you go can tell you a lot about how hydrated you are. Dark urine or not going to the bathroom very often could be signs that you need to hydrate more.

"Monitoring urine color is a good method, aiming for a pale yellow or 'lemonade' color," outlines Patel. "Urine that is dark or very yellow indicates possible dehydration, whereas if your urine is too clear, you might be overdoing it (on the water) and therefore not absorbing the fluid you’re consuming."

You also need to be careful about going overboard too. Yes, over-hydration—although rare for the average person—is a thing and might impact your salt and electrolyte levels causing serious complications. So, if your urine is clear with no color at all, you may want to back off of the water intake for a while.

Track Your Thirst

If you feel a need to quench your thirst, you are most likely already dehydrated. However, your body is equipped to signal when you need to drink. Just be sure to listen to what it is telling you.

Thanks to neurons in the lamina terminalis (located at the base of the brain) your body will signal to you that you are in need of water. The goal is to avoid feeling thirsty in the first place by keeping on top of your hydration throughout the day.

How to Drink More Water

Drinking enough for hydration sounds simple enough, but busy schedules, and even general forgetfulness, can interfere with how much water we drink in a day. If you struggle to drink enough water throughout the day, Patel suggests setting a timer to remind you when to take a few sips of water.

"Always keep a water bottle around to help encourage hydration," Patel says. "Adding flavor (such as with electrolyte tablets and powders) will encourage consumption, too."

Plus, electrolytes can help your body properly absorb fluids and nutrients. If you are pregnant or nursing talk with a healthcare provider to determine which electrolyte drinks, tablets, or powders are safe, and always check the label for hidden ingredients especially if you have allergies or sensitivities.

Tips for Staying Hydrated

  • Drink first thing: Hydrating first thing each day will set you up for the day ahead. A study of 12 men found that drinking 1500 milliliters of water in the morning receded fatigue and improved short-term memory, attention, and reaction. This suggests that drinking water in the morning, and remaining hydrated, can positively impact the remainder of your day.
  • Keep water close: Make your water bottle your new sidekick and pack it on the go to ensure you are never without a source of water. You may want to select a bottle that helps you track how much you are drinking during the day.
  • Try an app: There is a slew of apps, such as WaterMinder, that calculate and measure how many ounces of water you have swigged throughout the day.
  • Pace yourself: Rather than downing a few liters at once, drink in measured, spaced-out increments to avoid over-hydrating.
  • Drink during meals: Patel indicates that drinking water while eating also helps your body absorb the nutrients from the food you are eating and is an important part of staying hydrated.

Hydration Myths

There are a number of myths about hydration that can easily confuse what you thought to be true about hydration. For example, it may seem obvious that drinking water is key for remaining hydrated, yet water alone is sometimes not sufficient enough to fully optimize these levels.

In fact, according to Patel, your body also relies on electrolytes and a small number of carbohydrates to pull water into circulation for proper absorption. Talk to a healthcare provider or registered dietitian to see if you might benefit from adding electrolytes.

You also may believe that caffeinated beverages can dehydrate you. While it is true that their diuretic effect can pull water from your system and cause you to urinate more, the net water content in these drinks still counts toward your fluid consumption.

Another myth requiring debunking is that sleeping causes dehydration. In fact, as we sleep, the body falls into a natural cardiac rhythm that balances our hydration, and during the later stages of sleep, the hormone vasopressin is released to promote water retention.

This fact might explain why a wide-scale study on sleep duration found that shorter sleep cycles (under six hours) resulted in a higher occurrence of dehydration among U.S. and Chinese adults. This finding is important given that individuals sleeping less did not experience a hike in vasopressin which helps with water retention and instead experienced an increased likelihood of dehydration.

A Word From Verywell

When it comes to staying hydrated, in most cases you can simply increase or maintain your water intake. However, if you engage in extreme exercise or participate in endurance sports, you may need to add some electrolytes to the mix in order to maintain optimal hydration.

If, for some reason, you feel that you are getting dehydrated, increase your water intake. And, if you experience moderate to severe signs of dehydration like extreme thirst, constipation, dizziness, or rapid heart rate, see a healthcare professional right away. Ignoring signs of dehydration can have life-threatening consequences.

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