Can I Drink Too Much Water?

Our body needs water to function. With dehydration involved in everything from dry lips to poor sports performance, there is a lot of interest in how much water to drink every day.
While staying hydrated is important, drinking too much of this essential nutrient can lead to water intoxication, also known as water poisoning or delusional hyponatremia.

What is water intoxication?

Also known as water poisoning or delusional hyponatremia, it is, in simple terms, a potentially fatal disturbance of brain function resulting from an imbalance of the electrolytes due to excess water in the body.
This excess water can be due to excess oral intake or even iatrogenic (as in during certain surgeries or excess IV fluid administration).
This can lead to confusion, seizures, coma, and even death.

Why is excess water intake dangerous?

As you drink volumes that are more than what the kidneys can excrete, this water dilutes and reduces the amount of salt (hyponatremia) in your body; water gets pushed inside cells leading to edema.
In the brain, these swollen cells initially present as a headache, confusion, lethargy, and drowsiness, and as it worsens, even seizures and coma.
The brain encased in a non-expandable skull will ultimately result in increased pressure on it and the consequences thereof.
The direct cause of death in water intoxication is often brain edema.

How much water is too much?

• Acute intake of a large volume of water results in a rapid reduction in sodium levels and can result in symptoms.
• There are no specific numbers, but it depends on how fast you drink and how good your kidneys are.
• Generally speaking, water intake over 3litre (0.79 gallons) an hour can potentially lead to intoxication.
• The water excretion rate of a healthy adult is ~20 L/day (5.28 gallons) and does not exceed 800-1,000 mL/hr (0.21 to 0.26 gallons). Thus, a person with normal renal function can drink up to this amount without intoxication.
• It has been noted that most cases are not due to simply drinking too much water and is usually a combination of excess fluid with increased secretion of ADH (anti-diuretic hormone or Vasopressin), which signals the kidneys to store water. This is something that typically occurs when there is increased physical stress, like during a marathon or army recruitment exercises, resulting in kidneys conserving water even when the amount is in excess.

What are the symptoms?

• The initial symptoms are a feeling of unease, nausea, and vomiting.
• It can progress to confusion, headache, disorientation, hallucination, and delusion. These symptoms closely mimic a psychosis episode and may be missed in a case of a preexisting psychiatric disorder.
• Worsening cases might lead to seizures, coma, and even death.
• In children, look out for body swelling, clear urine, lots of diapers disproportionate to the usual number, lethargy, confusion, behavioral changes, seizures, and unresponsiveness.

Am I at risk?

• Athletes run a high risk. There have been multiple reports of marathon runners and army recruits suffering from water intoxication.
• Psychiatric conditions can lead to polydipsia, where the person feels compelled to drink lots of water. Very often, the caregivers can confuse the symptoms of water intoxication with psychiatric symptoms.
• There have been reports of Ecstasy (MDMA) users suffering from water intoxication due to the combined effects of the release of neurotransmitters that increase energy and metabolic rates and being in a hot environment like during raves and parties.
• Children less than a year old, esp. infants less than nine months, are a special category as awareness levels of water intoxication in children are often poor. There have even been reports of this following swim classes and the use of diluted formulas.
  ( WHO and AAP (American Association of Pediatrics) recommend exclusive breastfeeding for the first six months of life.)
• Iatrogenic (illness caused by medical treatment) cases have been reported during intravenous fluid administrations if not appropriately tailored. Other causes can be certain psychiatric medications and surgical procedures done for the prostrate and uterus. Speak to your treating doctor if this concerns you.

So, how much water should I drink every day?

This is a question with many answers and no consensus.

There are many recommendations, but for the general population, drinking as soon as you feel thirsty is an easy, safe, and acceptable method.

For athletes, the recommendations are different. The fluid that is lost due to sweating and breathing should be well compensated for as it can not only impact the performance level but also put them at risk for heat exhaustion. Athletes should not rely on thirst as an indicator.

Takeaway

• Water intoxication results from excess water intake, which leads to severe hyponatremia (reduced sodium content).
• Water intake over 3litre (0.79 gallons) an hour can potentially lead to intoxication.
• Athletes and children are a vulnerable group.
• While it is okay for the general population to drink when thirsty, athletes need special consideration.
• Initial symptoms are often nonspecific and can be easily overlooked. As it progresses, it can lead to seizures, coma, and even death.

Trivia

Five years after the demise of Andy Warhol (d1987), post what was a routine gallbladder surgery, his family blamed the hospital for causing his death due to excess fluid administration during the postoperative period. The autopsy weight of 68kgs (150pounds) vs. 58kgs (128pounds) during admission, along with findings of “ lungs filled with fluids and trachea brimmed with a pinkish froth, “ were cited as evidence.