How Much Water Should You Drink?

Make sure you’re staying properly hydrated, and take a moment to delve into why this vital elixir is more than just a thirst quencher.

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Last updated: Aug 14th, 2023
Full Glass of Water

We all know that feeling when life gets busy — so much so that we lose track of the simple things, like drinking water. But adequate hydration keeps us energized and healthy.

We all know getting enough water is extremely important for our health; the human body is made up of 45-75% water and relies on it to help support energy levels, maintain weight, and flush toxins out of the body. But do you know exactly how much of this vital substance you should be drinking per day?

If you don’t get enough water, you run the risk of becoming dehydrated, which can lead to other health complications like low blood pressure and kidney issues. However, different life circumstances and daily habits can impact how much water your body might need. Understanding the benefits of water, where your daily hydration might be coming from, and the dangers of dehydration are crucial steps to make sure you’re cultivating a balanced lifestyle.

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Health benefits of water

Water is an incredible resource that helps the human body function properly. Water does so many things for our bodies without us ever being conscious of it. Maintaining proper hydration can help you feel more energized, enhance mental focus, and improve your quality of life. Among many other benefits, water does the following things for us:

  • Carries nutrients and oxygen to cells.
  • Flushes bacteria and other toxins from the bladder.
  • Helps us digest food properly and avoid constipation.
  • Keeps blood pressure normal.
  • Protect joints by cushioning them.
  • Regulates body temperature.
  • Protects joints and organs.
  • Helps maintain sodium balance.

There are many ways your body can get the water it needs. Unless circumstances dictate that you receive intravenous (IV) fluids, drinking water will be the fastest and easiest way to hydrate. But it’s important to understand that you also receive hydration from other beverages you might drink throughout the day. Any drink that contains water can contribute to your daily total hydration. Some other options to help you stay hydrated include:

  • Coffee
  • Tea
  • Juice
  • Soda
  • Milk

The difference between these drinks and water is that water gives you pure hydration without anything extra. Coffee, tea, juice, soda, and milk will give you some hydration, but they also come with extra things such as caffeine, sugar, and/or fat.

Consuming fruits and vegetables is another way you can get water. Certain produce has more water in it than others, but all fruits and veggies you consume can contribute toward what your body needs. Cantaloupe, strawberries, watermelon, lettuce, cabbage, and cooked squash contain roughly 90%-99% water.

The benefit of eating vegetables and fruit with high water content is that the ingredients provide your body with healthy nutrients and hydration at the same time.

Calculating how much water you need per day

The average person loses about 8-12 cups of water per day through sweat, breathing, urine, and bowel movements. This makes it extremely important to replenish the water your body loses naturally.

The precise amount of water you need varies based on factors that include your sex, environment, activity level, and dietary choices. The Institute of Medicine’s recommended dietary allowances (RDAs) and adequate intakes (AIs) state the following:

  • Women should aim for 2.7 liters (about 11 cups) of water per day from food, drinking water itself, and other beverages
  • For men, this is increased to 3.7 liters (about 15 and a half cups)

The climate you live in will impact the amount of water you need to consume daily. If you’re in a hotter climate, you may perspire more than you would in a colder climate. Similarly, your activity level will impact the amount of water you need to consume. The more active you are, the more water you need to drink to replenish what you lose when you sweat from exertion.

If you’re on a high-fiber diet, you may need to drink more than the average amount of water needed to stay hydrated. The same is true if you’ve recently consumed high amounts of alcohol.

And if you’re breastfeeding, you’ll need more water than average, too. Although being slightly dehydrated may not affect your production of breastmilk, it’s likely to affect you negatively in other ways. During lactation, the Institute of Medicine recommends an intake of 3.8 liters per day (16 cups) of total water from food, beverages, and water itself.

How can you tell if you’re drinking enough?

Everyone needs varying levels of hydration, and because of this, it can be challenging to know if you are getting enough. One way you can tell you are getting enough water is by checking the color of your urine. If your urine is a pale lemonade color or clear, then you are getting enough hydration. If your urine is the color of apple juice or tea, you need to drink some more water.

Can you drink too much water?

It’s possible to drink too much water. Adequate hydration is important for the body to achieve biological stability even in the face of changing external conditions, yet it, too, is a factor that can disrupt that stability if you consume too much. Too much water can overwhelm the kidneys and dilute the sodium content in your blood, resulting in a life-threatening condition called hyponatremia. Hyponatremia can also be caused by underlying health conditions or the use of prescription medications.

What is dehydration?

One of the main benefits of drinking water is avoiding dehydration. Since our bodies are made up of 45-75% water, it’s important to replenish that water throughout the day.

What are the causes and signs of dehydration?

Getting enough daily water is very important for your body and your overall wellness. One of the main reasons someone becomes dehydrated is because they are not consuming enough water. This can be solved by making sure you drink more water throughout the day, following the guidance described earlier in this article.

Aside from not drinking enough water, there are outside factors that can also cause dehydration (such as being prescribed diuretics) or make you more susceptible to it. These factors include:

  • Lifestyle habits like diet, exercise, and activity level
  • Diabetes
  • Stress
  • Age
  • Medications
  • Excessive sweating
  • Fever
  • Diarrhea or vomiting

Dehydration is frighteningly common among older adults; close to 7% of people hospitalized over age 65 are discovered to be dehydrated.

Regardless of your lifestyle or age, water is an essential part of cultivating a balanced and healthy life. Without enough water, you might start to experience some of the following symptoms:

  • Dark urine
  • Thirst
  • Bad breath
  • Muscle cramps
  • Headaches or migraines
  • Dry skin
  • Low blood pressure
  • A decrease in sweat
  • Elevated cravings for sweet foods despite loss of appetite

Who’s at risk for dehydration?

Dehydration does not discriminate. Anyone can become dehydrated if their water intake is less than their water output. But some populations are at higher risk of becoming dehydrated.

Infants and children

Infants and children are at higher risk of dehydration because they are also the most likely to experience more frequent diarrhea and vomiting, which cause great loss of fluid. In addition, young children don’t understand what it means to be dehydrated and sometimes don’t convey their thirst quickly enough to avoid dehydration.

Older adults

The older you get, the harder it is for your body to retain water. Older populations also lose their ability to detect thirst accurately and are often on medications that impact hydration levels.

People with chronic illnesses

Diabetes puts those who have it at high risk of dehydration. In addition, when your body is fighting something, it is more vulnerable to dehydration because it is using up more bodily resources than normal. Medications that you routinely take for chronic illnesses can also make you more prone to dehydration.

People who work or exercise outside

Along with environmental factors, the activities people perform can greatly increase or decrease their risk of dehydration. Professional athletes take extra efforts to make sure they are staying hydrated and always have access to water or fluids. Any activity that causes us to sweat more also should cause us to drink fluids in response. Humidity prevents sweat from evaporating and cooling the body down, which in turn increases body temperature and the body's natural need for more fluids. If a person in this environment doesn’t consume more fluids in response, then that person can become dehydrated.

How to diagnose dehydration

A blood or urine test can tell your doctor if you are dehydrated. But apart from lab work, ask yourself, are you thirsty?

Most people assume, when they feel thirsty, that it’s time to drink water. Unfortunately, if you’re feeling thirsty, you are already dehydrated. Paying attention to your thirst levels can help you determine if you are dehydrated or not. It is better to drink small amounts of water consistently throughout the day — even when you don’t feel super thirsty — than it is to wait till you feel thirsty.

Levels of dehydration

There are different levels of dehydration that can determine what type of care you might need.

Mild dehydration

This means you haven’t had enough water on a particular day; it can be remedied simply by drinking more water. Drinking something that contains electrolytes can also help replenish fluids faster and can help if you have experienced any vomiting or diarrhea.

Moderate dehydration

Again, depending on age and underlying health, replenishing fluids at home could solve the problem, but you might instead require an IV, which hydrates you through your veins. If you have been experiencing diarrhea or vomiting for a considerable time and continue to experience it, for instance, you likely need this form of treatment.

Severe dehydration

If you’re severely dehydrated, you require medical attention at a hospital or in an ambulance. You’ll receive fluids via an IV, and professionals will monitor you for an electrolyte imbalance. Health professionals may administer acetaminophen to reduce fever and other medication to address the apparent cause of dehydration, such as diarrhea.

If a person is experiencing any of the following symptoms, it might mean that they are severely dehydrated and should call 911 immediately.

  • A fever of 103 degrees Fahrenheit
  • Muscle twitching
  • Red, hot, and dry skin
  • Nausea
  • Seizures
  • Lack of sweating
  • Confusion or altered mental state
  • Dizziness
  • Fainting
  • Hallucinations

Mental and physical effects of dehydration

Getting enough daily water is not only important for your physical health, but it can also impact your emotional and mental health. The severity of mental and physical consequences depends on the severity of your dehydration and ranges from mild inconvenience to life-threatening emergency.

When the body doesn’t have enough water, energy levels suffer, and we can become irritable. Dehydration can impair memory, vigilance, and ability to focus, while also increasing a person’s anxiety.

Along with mental and emotional complications, dehydration can affect you physically. Common physical complications from dehydration include:

  • Heat injury – This complication can range from mild heat cramps to heat exhaustion or life-threatening heatstroke.
  • Urinary and kidney problems – Our kidneys and urinary tract rely on water to filter out toxins and remove them from the body. The longer you go without proper hydration, the harder it becomes for your kidneys and urinary system to function.
  • Seizures – Electrolytes help communicate signals to the brain. If you don’t have the proper concentration of electrolytes, you can experience muscle spasms or even loss of consciousness.
  • Low blood volume shock – Dehydration can also lead to a low blood volume, which in turn leads to a drop in blood pressure and the amount of oxygen your body produces. This can be a serious, life-threatening condition.


Innerbody uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.

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