I remember a couple years ago, when my sister was starting to have acne problems, I came up with a brilliant solution. Since pimples are caused by pores being clogged up by dirt and other nasty things, why not block the pores before dirt even had a chance to sink in? So I told my sister to use vaseline (the container said that it didn't clog pores) to cover up her face, thus preventing blackheads. My sister, being the older, brighter one, agreed and before she went to bed she smothered her face with petrolium jelly... when she woke up she had the nastiest look on her face. She never did it again...