Flush review: Stop letting human faeces go down the toilet

Bryn Nelson’s extraordinary book asks why we let a vital natural resource, human faeces, get flushed away when we could be using it to heal guts, improve soil and understand our past

By Chelsea Whyte

Flush

Bryn Nelson (Hachette)

ASK me to name the world’s best invention, and I will always give the same answer: the toilet. Its ability to whisk waste away to a safe place where potential pathogens and odours can do no harm isn’t to be sniffed at. But an unusual book has convinced me that toilets make it too easy to waste our waste.

Bryn Nelson’s Flush: The remarkable science of an unlikely treasure explains the many ways …