If you're worried about going grey - try to relax. Scientists have found too much stress really does turn our hair white.
Researchers discovered the cells that give hair its colour disappear when the body is exposed to stress hormones.
And unfortunately for those affected, these "colourful" cells are unlikely to return, leaving the hair grey for good.
How do we know this? US scientists carried out experiments on mice which showed the startling effect that stress has on our hair.
They began with the premise that when the human body is injured, stem cells responsible for producing melanin - the dark pigment that protects us from sunlight - move from hair follicles to the skin, to help limit the damage.