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How long can a human go without peeing?

When nature calls, it's generally a good idea to obey when convenient, but by knowing your bladder means you could go longer than you think without a wee.

By Luis Villazon

Asked by: Ben Warwick, Poole

The bladder holds 400-600ml of urine. Normal urine production is around 1.5 litres every 24 hours, so that would give you nine or 10 hours to completely fill up.

However you can drop to as little as 400ml of urine production a day for short periods without suffering harmful consequences. This could conceivably give you as long as 36 hours between trips to the loo.

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Luis Villazon

Q&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.