7 Your Teeth Are Yellowish Dental hygiene has come a long, long way since we were kids. There's no need to get all Ryan Seacrest-y and obsessive about your megawatt smile, but there's something about yellowish teeth that says "Dust Bowl-era dirt farmer," and that's not an association you want people to have when they see you. Crest White Strips are these contraptions that a lot of ladies use very occasionally (less frequently than eyebrow-plucking, to give you a sense) that actually work to whiten your teeth. Again, you can do this in the privacy of your home, while watching TV. No one has to know. This is a classic lazy-not-ugly problem that guys have without even realizing it.