Is White Flour Bad To Health?

my girlfriend age 71 has ben eating white bread most of life her current doctor told her to stay away from white flour, i told her the same info she can't understand why she would have to change after all these years she has allergies and problems with facial skin something called roseea this word might be spelled wrong her energy level is very low as far as i know she has been on a southern diet n. carolina and has nothing but white flour, i mentioned rye and other breads and she never has anthing but white her doctor today told her to stop white flour items i stopped them quite some time ago can you advise me what she can do