Some people have red urine and faeces after eating beetroot, but how much do we know about beetroot's ability to intensify the colour of blood, thereby making blood stains impossible to remove?

One summer evening in 2004 our 11 year old son went to bed after various delaying tactics—arguments about friends who stay up later, forgetting to brush teeth, coming down for a drink of water. Shortly afterwards the dining room door opened. In he came, cupping his bleeding nose in one hand as he gripped the bridge of the nose with the other.

Beetroot—loved and despised for its lasting red colour

Credit: SUSANNAH BLAXILL/http://www.blaxill.com/

We led him to the kitchen sink to help him clean up and stem the bleeding. Oddly, though, the blood on …