This is the BBC.

Hello and welcome to more or less on the BBC World Service.

I'm Wesley Stevenson.

This week we're going to bust some myths about water. We're always being told

how much we should drink and what the benefits are of drinking lots of water.

But be prepared to find out that a lot of the stuff you're being told is wrong.

There's a lot of advice around but the thing that a lot of people remember is the 8 by 8 rule,

that you should drink 8 ounces of water, that's around 230 milliliters, 8 times a day.

We're told it will wash out toxins, give us better skin, prevent certain diseases.

But will it really? One man who knows is Dr. Stanley Goldfarb,

professor of medicine at the hospital of the University of Pennsylvania and an expert in kidney disease.

So let's start with that 8 by 8 rule.

Well, that volume of water actually came from an analysis that found that the average male takes in about 2.5 courts, about 2.5 liters, of fluid

per day.

The average woman takes in somewhat less, given their smaller size, about two or so. If you look at how much

water eight glasses a day would be each of eight ounces, it comes out to about that much.

So what happened was people sort of confused the idea

that this is the required intake.

And the other confusion that occurred

was then people said it's not so much

that you should take in eight ounces eight times a day,

but rather you should do that in addition to whatever fluid that you consume in association with your diet and with meals.

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