Webblackheads are usually caused by a pore that gets clogged with keratin (skin protein) and sebum (oil). Given the black color many believe these spots are clogged with dirt, but. If you’re curious but a little squeamish, a good first watch is a blackhead video. Webdec 21, 2020 · when dermatologist sandra lee, md, a. k. a. Pimple popper, says she's excited about a pop, you know to drop everything and grab your phone.