Do you really know what you’re putting on your hair? Many hair dyes you can buy in the shops or hairdresser contain toxic chemicals that can cause skin problems or even increase the chances of DNA mutations (a potential cause of cancer). As a result (and to save money), many people are turning to supposed natural alternatives, with the internet showcasing a plethora of home-made and plant-based concoctions. Yet very few of these provide much evidence that they colour hair.