If you pull 1 grey hair out, 2 will grow back
When you notice a stray grey hair, you may pull it out. This action can damage the hair follicle and the replacement hair that will eventually grow takes longer to regenerate. By the time it does, another grey hair is beginning to grow next to it. Then when the hair that was originally pulled out does regrow, you have two grey hairs. If this myth was true, pulling out grey hair would be an excellent way to make your hair thicker! Unfortunately, it's not and can do quite the opposite.
Grey hair is coarser than other hair
Grey hair may be drier because hair usually goes grey at an age when the oil flow begins to be reduced. This can give the illusion of it being coarser, but hair gets finer as we age, so unless you turn grey very young, grey hair is usually not coarser.
Hair can turn white overnight
Scientifically, it is an impossibility. The myth may have started with alopecia areata, whereby clumps of hair fall out and are either replaced with white hairs, or leave only existing white hair behind. However, this can’t occur overnight. It is one of those statements used to convey the degree of stress somebody has undergone. Stress can affect the hair colour gradually as the hair is growing, but certainly not overnight.