Is It Possible to Drink Too Much Water?

We all know drinking water is good for our health and bodies. However, have you ever thought, “how much is too much water?”

Water Intoxication

When your body receives too much water in the body, this process is called water intoxication and can disrupt brain function. Drinking a lot of water increases the amount of water in your blood. When the water disputes the electrolytes in your blood, especially sodium. According to the US National Institutes of Health, when sodium levels fall below 135mmol/L, it is called hyponatremia.

Sodium is used to balance fluids between the inside and outside of a cell. When sodium levels drop, due to water levels in the blood, the fluids shift from the outside to the inside of the cell causing them to swell up. When this happens, it can be a  life threatening issue.

water intoxication
Man holding his head after drinking too much water.

Dangers of Drinking Too Much Water

Water intoxication results from the swelling of cells.

When brain cells swell, pressure inside the skull increases. This pressure causes symptoms of water intoxication, which include:

The next level of serious symptoms are:

  • Increased blood pressure.
  • Confusion.
  • Double vision.
  • Drowsiness.
  • Difficulty breathing.
  • Muscle weakness and cramping.
  • Inability to identify sensory information.

Excess fluid accumulation in the brain is called cerebral edema, which can affect the brain and cause central nervous system dysfunction.

In severe cases, water intoxication can cause brain damage, seizures, coma and even death.

Can Drinking Water Kill You?

Believe it or not, yes, water can potentially be fatal if you drink way too much of it at once. You have a greater risk of developing water intoxication if you drink a lot of water in a short period of time. The risk is less if you drink the same amount over a much longer period of time. But it’s very rare and usually only applies to those that are exercising excessively such as sports athletes or soldiers out in the field.

The kidneys are capable of excreting up to 7 gallons (28 liters) of fluid per day. However, they cannot excrete more than 1 liter per hour. Therefore, drinking more than this is not a good idea. So If you’re really thirsty, try spreading out a glass every so often or eat beforehand.

This is also why it’s very common for sports athletes to consume sports drinks that contain electrolytes. This replenishes the lost sodium levels in the blood and it helps avoid water intoxication altogether. You can avoid the sugar in sports drinks by trying our Evolve electrolyte-enhanced water. It’s great for the summers in the Arizona, when dehydration and water intoxication become a serious issue.

sports athletic track runner
Runner setting off on a track at full speed.

How Much Water is Enough?

There is really no direct recommendation of water, but a general rule of thumb is 8 glasses of water per day. However, this can vary with weight, sex, age, how much you exercise and the climate in which you live in. If you want a closer estimate, try diving your body weight in half to get the amount of ounces you will typically need a normal day. All in all, listen to your body. If you’re thirsty, it’s probably time to drink some water. You can view our post on, “How Much Water Do I Really Need to Drink Daily” to get more information on the topic.