Eight Glasses of Water

July 11, 2008 – 12:37 am

Despite findings that it's a silly recommendation there are still people who suggest that you drink eight 8-ounce glasses of water a day for weight loss or colon health or proper hydration.

One of the trains of thought I read on this is that people lose 10 cups of water a day, get 4 cups from foods, and need to drink 48 ounces of water to make up the defecit, but since we drink so many caffeinated beverages which act as diuretics (make us lose more water), we need to actually drink 8 cups to make up for the added water loss.

I'm not concerned so much with what is right and what is wrong, but more with the rough equivalents for 8 cups of water a day. Right off the bat, that's 2 quarts or 1/2 gallon. So it's being recommended that you drink 3.5 gallons per week, 182.625 gallons per year (365.25 days). At that pace, how long would it take to drink all the water in an Olympic size swimming pool?

We know that the official volume of an Olympic size swimming pool is 2500 cubic meters, which equals 2,500,000 liters. If a gallon is 3.785411784 liters, then it's recommended that you drink roughly 691.31 liters a year. At that rate, it would take you 3,616 years and 118 days (or 1,320,862 days) to drink up every last drop in an Olympic size pool. Or, as a reservoir, an Olympic size pool holds enough water to meet the daily drinking water needs of 44,028 people for a month. Of course, when you add in toilet-flushing water, bath water, clothes-washing water, landscaping water, and shaving-in-the-shower water it probably lasts an American family of four less than a year.

If you take a 10-minute shower under a water-saving nozzle that limits the flow to three gallons per minute, your shower used as much water as 60 days of drinking 8 cups a day. If your toilet uses 2 gallons and you flush 5 times a day, you use 20 days worth of water. And remember, there are experts who are saying you only need 4-6 cups of water a day. At 6 cups of water a day, that showering and toilet flushing would use up 106.6 days worth of water instead of 80.

Of course, we can also convert a year's worth of 8-glasses-a-day into its equivalent volume. At 231 cubic inches per gallon, 182.625 gallons is 42,186.375 cubic inches or 24.413 cubic feet of water. While it's nowhere near enough to fill an Olympic size pool, it's enough to fill a bathtub that is 4.5 feet long, 2.5 feet wide, and 2 feet deep.

What Rough Equivalents can you come up with for 8 glasses of water a day? Post them in the comments section below.