Do you need 8 glasses of water a day?

Everyone's heard this bit of conventional wisdom and some folks struggle awfully hard to maintain it - but do you actually need 8 glasses of water a day? The answer is a simple "NO".

Nobody seems to know where this health myth originates, but it is not based on scientific evidence. For most people, having a drink when thirsty is enough to meet daily liquid requirements. Pushing oneself to drink additional water is not only unecessary, but can be damaging to your health. Water intoxication occurs in extreme cases and can result in altered mental states and death.

• Woman dies after taking part in "Hold Your Wee for a Wii" competition (a water drinking competition).