How Much Water Is too Much?

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It is important to stay hydrated. However, excessive fluid consumption does not contribute to your well being, and may even cause health problems.

Excessive fluid consumption can cause fluid overload, or water intoxication, which may lead to serious health consequence—swelling of the brain, brain injury, and ultimately stroke—leading to disability or even death.

It is not only the amount of water consumed that causes overload—water toxicity is caused by drinking too much water too fast. Most people who overdose on water are not aware of the consequences. Drinking too much water may initially produce mild consequences, and then, if the situation continues, dangerous health effects may occur.

The Consequences of Drinking too Much Water

Going to the Bathroom too Much—Constantly Peeing

Your body works to maintain normal function despite the regular variations that you experience throughout the day. The first way your body manages water overload is by simply getting rid of the excess fluid through urine. This means that if you drink too much fluid, you will balance out your body's fluid by urinating more. If you repeatedly drink more water than you need, then your body should be able to efficiently remove the fluid, and you will end up constantly peeing.

If you notice that you are constantly peeing and constantly thirsty, this can be a sign of diabetes (a problem with your pancreas that results in a buildup up blood sugar.) Your body manages the buildup of blood sugar in a very complex way, and frequent urination and constantly feeling thirsty are among the earliest signs of diabetes.

Dizzy Spells From Drinking too Much Water

If you drink too much water to the point that your body cannot get rid of the excess fluid fast enough, then you will begin to feel the physical effects of the excess fluid. When your body becomes overwhelmed with excess fluid, your electrolyte concentration becomes unbalanced. As your body attempts to cope with the fluid and electrolyte imbalance, you may begin to feel dizzy.

This dizziness is a sign that your body is being pushed too far. But, generally, dizziness caused by water overload does not indicate permanent brain damage. However, if you continue to drink so much water that you cannot adequately eliminate it fast enough, permanent brain damage may occur.

How Does Water Overdose Cause Brain Damage and Stroke?

The rapid consumption of large amounts of water overwhelms the body’s natural ability to maintain normal fluid balance. This causes excess fluid to enter into the brain, resulting in brain swelling. Symptoms include sudden unexpected loss of consciousness, seizures, or stroke.

When the body takes in extreme amounts of fluid, the excess water literally flows into the brain cells through a process called osmosis. This causes brain tissue compression and lack of normal function. Brain cells may experience a disruption to their normal calcium and sodium concentration and begin to function abnormally. Some brain cells may die from physical compression and some from the electrolyte and water imbalances. This condition—hyponatremia—is very difficult to manage medically because it progresses so rapidly and the damage is so severe.

Severe sodium and water imbalances affect a specific area in the brainstem called the pons and may cause a syndrome called central pontine myelinolysis or locked-in syndrome, which results in flaccid weakness of the whole body.

Why Would Anyone Drink Excessive Amounts of Water too Fast?

There are, in fact, some circumstances that set the stage for water overdose.

Health Cleanse

The idea of drinking water because it is pure and devoid of calories is popular among dieters and health enthusiasts. Overall, water has many benefits when it comes to healthy living. But the advice to 'drink more water,' doesn't apply to everyone.

The ideal amount of fluid consumption for an average person should be between 9-12 cups per day.

People who already consume enough water do not need to drink more. In general, thirst is a reliable indicator of the body’s water requirements. Some health conditions such as diabetes and kidney disease may disrupt your normal thirst mechanism and necessitate a consultation with a dietitian or physician to set guidelines for fluid intake.


It is normal for athletes to drink fluid in order to replenish and cool off during and after a training session and it is important for the body to stay hydrated during exercise. However, in the setting of extreme physical exertion, thirst may not be the best guide. Devoted athletes who work out beyond moderate levels should obtain professional guidance regarding appropriate fluid replenishment.

Water Games

These activities often seem silly or harmless to young people. Yet some actions that seem innocuous may be quite dangerous. Preschool-aged children and older kids—even as old as college-aged young adults—may think it is funny to challenge each other to drink large amounts of water or other liquids (such as alcohol, which contains mostly water) quickly. But these fun games have unfortunately been known to harm some of the kids who participate in them.

Water overload has been responsible for incidents of brain damage and death in children, teenagers and young adults who play games involving exaggerated fluid drinking or who use rapid consumption of excess water or fluid in hazing and initiation rituals. The outcome is usually shocking to young witnesses, which can further delay appropriate medical attention and treatment. Thus, the damage may be permanent paralysis, mental incapacity or death.

A Word From Verywell

Most of the time, good for you means good for you. However, in some instances, too much of a good thing is really too much. Diets that can help you lose weight can have negative effects on your overall health. And, surprisingly, you can even overdose on harmless and healthy things such as water and vitamins.

The key to a healthy lifestyle is balance and moderation. Take care of your health by seeking out trustworthy and reliable sources.

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