You may not know it but you can be drinking yourself to death. The idea here is to balance the amount of water you have been drinking with what you have been sweating. This literally includes sports drinks, which when consumed in excessive amounts may cause hyponatremia. To make a long story short, if you are sweating 500 ml per hour, that is what you should be drinking!
Drink to your thirst. It is the best indicator. That is the easiest way to determine how much water you should consume.
At any instant, water escapes the human body through urination, sweat, defecation or exhaled breath, and many other routes. Although it is essential to replace these lost stores, there is such a thing as fatal water overdose.
In 2007, a 28 year old woman died after competing in a water drinking contest. She downed about 6 liters of water in 3 hours. When she got home, she vomited, had a splitting headache and then, died from so called water intoxication.
In 2005, one study found that close to 1/6 of marathon runners develop some degree of hyponatremia, called as dilution of the blood, caused by drinking too much water. Going overboard to rehydrate is also common among endurance athletes.
What about hyponatremia? This means having insufficient salt in the blood or having a blood sodium concentration below 135 millimoles per liter or 0.4 ounces per gallon. Severe cases of hyponatremia can lead to water intoxication.
Symptoms can be headache, fatigue, nausea, vomiting, frequent urination and mental disorientation. When a person drinks too much water in a short period of time, the kidneys may not be able to flush fast enough, thus making the blood waterlogged.
Because it is drawn to regions where the salt concentration and other dissolved substances is higher, the excess water leaves the blood and ultimately enters the cells. The cells swell like balloons just to accommodate it.
Swelling or brain edema can be disastrous. The common manifestations of swelling are seizures, coma, respiratory arrest, brain stem herniation and death.
One study observed that drinking 8 ounces of glass of water per day for healthy adults living in temperate climates and doing mild exercise could be harmful. It can lead to potential hyponatremia, besides, it makes people guilty of not drinking enough.
Drinking an extreme amount in a short time can be dangerous. Hyponatremia is very serious and can be fatal. It is often referred to as water intoxication.
When you drink a bottle of water every now and then, but you are having an exercise or are sweating and urinating, you may still be fine. However, drinking way too much too fast may lead to death.
The warning signs can be the same that of a heat stroke and exhaustion. Other known symptoms may include diarrhea, nausea, vomiting, feeling hot, headache and just feel crummy.
Ballantyne, C. (2007). Strange but true: Drinking too much water can kill.
Keep this in mind, although your cells and organs in the body need water to function properly, excessive drinking may lead to hyponatremia. The excess water dilutes the blood sodium levels and causes the fluid to move inside the cells, making it swell. Drinking too much water increases pressure inside the skull and can be fatal in severe cases.
The kidneys are capable of excreting up to 7 gallons or about 28 liters of water per day only. They cannot excrete more than 1 liter per hour. Too much water and too little salt dilutes blood salt levels below the normal range.
Any sudden drop in blood salt levels due to drinking too much water than the body can excrete, causes all cells in the body to swell. Dark colored urine merely reflects water conservation by the kidney, rather than the body lacking water. The mechanism of thirst is not quite understood today and the non-regulatory drinking is often associated to the capacity of the kidneys to rapidly eliminate excesses of water or reduce urine secretion to temporarily hold and retain or economize on water.