Most of us grew up hearing that we need to drink at least 8 glasses of water a day to stay healthy. But experts now warn that drinking water in this quantity isn't good for you and may actually be harmful.
We've been told that drinking 8 glasses of water a day does wonderful things your your health — preventing urinary tract infections, improving the quality of your skin, helping with weight loss and digestion, and increasing concentration.
But the study disagrees and says that not only does drinking 8 glasses of water a day not deliver on those health benefits; it can also have detrimental effects, such as hyponatremia, a low-blood sodium condition common to marathon runners.
"If you're drinking excessively, if you're drinking beyond comfort, your kidneys are actually having to work very, very hard," McCartney said.
At every moment, water is escaping from your body through sweating, going to the bathroom, or even exhaling. Replacing lost water is important, but rehydration can be overdone and there is such a thing as water intoxication. If you drink too much water in a short period of time, the kidneys can't flush it out fast enough and the blood becomes waterlogged.
The symptoms of water intoxication include headache, fatigue, nausea, vomiting, frequent urination, and mental disorientation. Generally, the people who die from too much water are those who participate in water drinking contests or athletes who mistakenly over-hydrate when training.
So, if you shouldn't drink the "recommended" 8 glasses of water a day, how much water is safe to for you to drink?
The Mayo Clinic recommends you drink enough fluids that you never feel thirsty, and so you can produce 6 cups of colorless or slightly yellow urine per day. In other words, use your head when it comes to drinking water, and don't over do it.
Too much of a good thing, even when it's water, can be dangerous.