How much water do you need

About 60% of the human body consists of water. Water serves to keep all your body systems working properly.

But you may be wondering: Exactly how much water should I drink? And can I ever drink too much water?

Why Is Water So Important?

Your body needs water to survive and serves many functions in the body, including:

  • Helping your body maintain a normal temperature.
  • Aids digestion.
  • Helps your heart work efficiently.
  • Keeps your kidneys working properly and helps prevent kidney stones.
  • Helps you maintain a healthy weight.
  • Gets rid of wastes through urination, bowel movements, and perspiration.
  • Keeps your joints lubricated and cushioned.
  • Protects your spinal cord.

Some of your daily fluid intake can come from other no-calorie beverages, like sparkling water and herbal teas. You can even include modest amounts caffeinated coffee and tea. The Food and Drug Administration (FDA) says you can safely consume 400 milligrams of caffeine (about four cups of coffee) daily. If you are sensitive to caffeine, you may want to stick to decaf coffee or herbal teas.

Fruits and vegetables like watermelon and cucumbers contain high amounts of water, which can count toward your daily fluid intake. But it’s hard to measure how much fluid you get from food.

Try to not substitute soda or energy drinks — or even fruit juice — for water. They are high in calories and packed with sugar and additives. If you do not enjoy plain water, try adding a dash of lemon or lime juice for flavor.

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How Much Water Should I Drink?

Different people need different amounts of water during each day. How much water you need can vary depending on your sex, size, activity level, and age.

According to the Academy of Nutrition and Dietetics, there are some general guidelines. The average woman needs about nine cups of water per day. Men need about 12.5 cups of water per day.

One of the easiest ways to tell if you’re getting enough water is if you’re thirsty. You can use thirst as a guide for fluid intake. If you are experiencing symptoms such as headache, dry mouth, dizziness, or general unwell feeling, these are usually late signs of dehydration.

You may need more water if you are:

  • Pregnant or breastfeeding.
  • Living in a very hot climate.
  • Exercising and sweating profusely.
  • Running a fever.
  • Suffering from diarrhea.
  • Vomiting.

Ask your doctor about the right daily amount of water for you.

What Happens When You Don’t Drink Enough Water?

If you regularly consume less water than recommended, you may suffer from the following problems.


If you lose more water than you take in, you get dehydrated. Dehydration can cause headaches, dizziness, and digestion problems. You might feel confused or light-headed.

Severe dehydration can lead to kidney failure, heart problems, seizures, and death.

Urinary tract infections

Without enough water to flush out your urinary system, you are more susceptible to infection.


Your bowels need water to function properly. Not enough water leads to hard, packed stools, which leads to constipation.

Kidney stones

Kidney stones form when there’s not enough water flowing through your kidneys. Crystals in your urine harden into irregularly-shaped objects called kidney stones. Kidney stones can get stuck in your urinary system, causing painful blockages.

Can You Drink Too Much Water?

It is very rare, but it is possible to drink too much water. But it is usually only a concern for high-performance athletes (like marathon runners) who drink large quantities of water quickly. Your kidneys can only get rid of about 32 ounces (about four cups) of water per hour.

The problem with drinking so much water quickly is electrolyte balance. The excess water dilutes the electrolytes — essential minerals like sodium — in your blood and causes the cells in your body to swell. The swelling can negatively impact your brain.

Symptoms of overhydration are similar to dehydration. They may include confusion, headaches, and seizures.

Some athletes opt for electrolyte drinks that contain sodium, but they are not necessary for the average person. Ask your doctor if you are in doubt about your hydration needs.

How to Get More Water into Your Diet

Some people have a hard time drinking enough water. They may not love the taste, or they find it inconvenient. Here are some ways to boost your water intake.

  • Do not ignore your thirst. You should reach for water anytime you feel thirsty.
  • Swap energy drinks and soda for water.
  • Carry a water bottle with you and sip throughout the day. Refillable water bottles come in all shapes and sizes, so you can find one that works for you.
  • Freeze disposable water bottles and keep them with you for ice-cold water all day.
  • Choose water when eating out.
  • Add lemon, lime, or a fruit slice to your water. A little extra flavor does not add many calories and may make plain water more appealing.
  • Make it a habit to serve water with meals at home.

Once drinking water becomes a habit, you will find it easier to squeeze more into your daily life. You may even learn to love the taste.


CDC, Get the Facts: Drinking Water and Intake, Link

CDC, Water and Healthier Drinks, Link

Academy of Nutrition and Dietetics, How Much Water Do You Need, Link

EPA, Bottled Water Basics, Link

Department of Health and Human Services Office on Women's Health, Water, Link

FDA, Spilling the Beans: How Much Caffeine is Too Much? Link

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