Strange but True: Drinking Too Much Water Can Kill By Coco Ballantyne

http://scientificamerican.com/article.cfm?articleID=4EC337D6-E7F2-99DF-3549D1F6684BC11A&chanID=sa011







Living water is the main component of life. It inhabits 66% of the human body, running through the blood, in cells, and everywhere in between. Though replacing the water lost during urination, perspiration, etc., rehydrating yourself could potentially be fatal.


One example is when, earlier this year, a woman entered a water chugging contest and consumed about six liters of water. After the contest she regurgitated and had a terrible headache later in the day. She unfortunatley died to what is called intoxication by water. Another example is of a young man who was forced to drink a great amount of water during his hazing process. Also people who are looking for a fun night at the club and use ecstasy tend to over-hydrate themselves and death is common. Lastly it is common among endurance atheletes.


In 2005 the New England Journal of Medicine found that some of the runners developed a form of hyponatremia or dilution of the blood from too much water. In Greek and Latin it means "insufficient salt in blood". In severe cases of hyponatremia it may lead to water intoxication, which include headache, fatigue, nausea, frequent urination, and mental disorientaion.


The kidneys control the amount of water, salt, and solutes that leave the body by pumping them through tubules. But if a person consumes a lot of water in a short amount of time it is hard for the kidneys to flush it out quick enough and the blood becomes "water-logged". Then the excess blood leaves and enters the cells, which in turn, swell. Cells that are planted in flexible tissues, such as muscle and fat, so they have room to swell a bit. This , however, is untrue for neurons. An example is the brain which does not have room to swell because the blood and cerebrospinal fluid also need space. Therefore, brain swelling can be disastrously fatal. M. Amin Arnaout, chief of nephrology at Massachusetts General Hospital and Harvard Medical School, says that "Rapid and severe hyponatremia causes entry of water into brain cells leading to brain swelling, which manifests as seizures, coma, respiratory arrest, brain stem herniation and death".



So how did we come up with the idea that drinking a lot of water is healthy? Heinz Valtin, a kidney specialist, decided to tackle this one by seeing if eight, eight ounces of water was truthfully healthy. After studying he found that no scientific studies have said that to be true. Valtin also said, in his 2002 review in American Journal of Physiology—Regulatory, Integrative and Comparative Physiology, "could be harmful, both in precipitating potentially dangerous hyponatremia and exposure to pollutants, and also in making many people feel guilty for not drinking enough".



However, water poisoning does not always have to do with drinking too much water but also the amount vasopressin (hormone) secreted, explained by Joseph Verbalis (chairman of medicine at Georgetown University Medical Center). This tells the kidneys to conserve water.



'While exercising, "you should balance what you're drinking with what you're sweating," and that includes sports drinks, which can also cause hyponatremia when consumed in excess, Verbalis advises. "If you're sweating 500 milliliters per hour, that is what you should be drinking."' But how can you measure your sweat outtake while your exercising? As long as you're healthy and mindful you should "drink to your thirst. It's the best indicator. "


My Thoughts: I think that this article was interesting and it caught my eye. It also made since that too much water good hurt you, after studying hypotonic solutions which cause the cells to swell and sometimes burst. It was well written except for the couple of things that seemed to be unnecessary.