Is dandruff infectious?
So far as we know, this mast annoying trouble is riot infectious, If you have it you are not likely to give it to anyone else nor are you likely to catch it from a dandruffy friend. It is not even proved that dandruff is caused by any kind of germ or bacteria.
Dandruff is caused by over active oil glands at the roots of the hair. Too much of this oil pours out onto the surface skin of the scalp. It clots and mixes with the deadskin cells that would normally fall away without being noticed. The annoying flakes of scuff are thought to be a mixture of this oil with dead skin cells.