Then there is a video transcript.
Narrator: What do you think of it when you hear the word poison? Arsenic? Cyanide? What about water?
Life could not exist without water. But under the right circumstances … Water can be as dangerous as any poison.
This is what happens when you drink too much water.
Your kidneys filter out excess waste and water from the blood. But they can only treat 800-1,000 mL of water per hour. And if you somehow manage to drink more than that without throwing it, you can run into trouble. Because drinking faster than your kidneys can transform it. So the excess ends up in your cells.
Normally, your cells are surrounded by an accurately balanced solution of sodium and water, which flows in and out through small holes in the cell membrane, thus keeping the sodium concentration both inside and outside the cell balanced.
But when you drink too much water, the sodium solution dilutes. It’s not salty enough. Thus some of that extra water rushes into the cell to restore balance and make it swell.
Doctors call this water intoxication and it is a major problem. Now, most of your cells can handle the swelling at some point since the soft, flexible tissue like fat and muscle can stretch.
But for the cells in your brain, it’s another story, because your skull isn’t stretched.
It’s bone. It’s hard – like a rock.
Thus, when your brain swells, it accumulates pressure in your head.
At first, you may experience headaches, confusion or drowsiness.
But when the pressure rises, you risk brain damage, coma, and even death. And it could all be finished in less than ten hours.
A 64-year-old woman, for example, died the same evening after drinking between 30-40 glasses of water. And a group of U.S. Army apprentices immediately vomited and took it after dropping more than 2 liters an hour after a hard day of training.
But it’s the marathon runners who have to be particularly careful. One study found that 1 in 6 marathons developed at least one mild intoxication from the water because the race stressed their body, including the kidneys. Therefore, they do not eliminate water efficiently, which can cause water to seep into the bloodstream more easily.
People with certain kidney problems are also vulnerable since they cannot properly treat water and the problem is not unique to water.
For example, the same thing can happen if you make too much beer at a time. It’s called potomania.
The good news is that there is an easy way to stay safe. The average healthy adult needs about 3-4 liters of water a day. And since this can come from food and even other beverages, drink it when you’re thirsty, and then stop.
EDITOR’S NOTE: This video was originally published in November 2018.