The mystery of why human hair turns grey as we age has finally been solved by a team of European scientists – and wisdom has nothing to do with it.

Science Daily reports that greying hair is caused by a massive build-up of hydrogen peroxide – the chemical women have long used to dye their hair blonde – due to wear and tear of hair follicles.

The build-up of peroxide eventually blocks our normal synthesis of melanin, the natural pigment responsible for our hair, skin, and eye colour.