Keats added a post in a topic bread causes acne
It's not the bread itself, it are the simple carbohydrates.
Here is your acne solution!! http://www.iinr.org/specialreports/ACNE.PDF
edit: actually, whole grain (rye) bread is a very low inducer of insulin, so the part of bread causing acne does only count for other variants of bread (white bread, etc)