I've had a lot of trouble with acne on my chin. Over the holidays, I spent some time in the mountains, eating, shall we say, horribly, but getting sufficient sleep and greatly reduced stress. The acne disappeared. Within days of the return to regular life--and better food--the acne is back.
Apparently, I need to work on sleep and rest, because no change in eating or cleansing has helped.
Started PB late 2008, lost 50 lbs by late 2009. Have been plateaued, but that thing may just be biting the dust: more on that later.