Can you drink too much water?

Asked by: Graham Burgess, Pembrokeshire

Yes. Your digestive system is capable of absorbing water as fast as you can drink it, but the kidneys of a healthy adult can’t remove more than about 900ml per hour. If you drink a litre of water an hour, the excess will accumulate in your cells and the spaces between them. This can dilute the sodium levels in your blood (called hyponatremia) and eventually lead to seizures and cardiac arrest.

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