The long-running series in which readers answer other readers’ questions on subjects ranging from trivial flights of fancy to profound scientific concepts

I lose at least half a pound in weight in the shower. What’s going on?

If I weigh myself naked before taking a shower and again immediately afterwards, my weight has always dropped by at least half a pound (approximately 200g) and sometimes by over a pound. It can’t all be dirt. I rarely take as long as five minutes in the shower so I can hardly have sweated off that much. Why does this happen?

John Malcomson, Sheffield

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