Why do brushing make the hair shine?

shiny hair

Mothers used to instruct their daughters to brush the hair at least 100 times before going to bed,
promising with tresses shinning brightly. Obedient girls were well rewarded: their hair did indeed take
on an attractive sheen.

The reasons for this were once thought to be the polishing effect of the bristles, likened perhaps to
that of a mild abrasive on metal. In fact, brushing stimulates oil glands in the scalp, making the hair
more shiny; also it helps to remove dust and dandruff that might otherwise give the hair duller
appearance. But don’t be overzealous. Trichologists warn that too much brushing, especially with a hard
brush, will do more harm than good, thinning the hair and splitting the ends.