So a blackhead is essentially a clogged pore. What we talk about when we say we're going to prevent blackheads, we are just preventing clogged pores. A few different ingredients can be in this. An alpha, beta, or polyhydroxy acid can be helpful, as well as a prescription retinoid, like Retina-A, Tazorac or Atrolin. If you don't have access to a prescription, you can use an over-the-counter retinol product as well. A gentle exfoliation once a week is fine, but make sure that what you're exfoliating with is fine-grained and don't over scrub. I also recommend not using any products that have mineral oil. Natural oils, like jojoba, argan, and coconut oil are actually fine. Lastly, if you like to use natural products, I like the ingredient Mahonia, M-A-H-O-N-I-A. This is sort of a natural pore unclogger, if you will, that can work very nicely.