You brush twice-sometimes three-times a day, you've slapped on a few Crest Whitestrips, and you opt for white wine instead of red at parties. And yet, your teeth are still not nearly as white and bright as they could be. That's probably because you're making one of these three common mistakes. Don't worry, though, we got you covered. Here's how to fix them.
1. You rely on a whitening toothpaste. Toothpastes can claim to be whitening without actually containing any bleaching ingredients. That's because they often just contain silica, a scrubby ingredient that removes the stains on the surface of your teeth but not the ones in the enamel. Meaning you won't do any damage to those decade-old coffee stains. One exception? The new Luster Premium Power White Deep Stain Eraser Toothpaste, which contains 2 percent stabilized hydrogen peroxide. "It should work better than other whitening toothpastes," says cosmetic chemist Ni'Kita Wilson.

2. You always brush your teeth with toothpaste before using whitening strips. We get it: Bleach strips don't exactly taste good, and you don't want to walk around with an unbrushed mouth. But brushing your teeth before you whiten can do more harm than good (heck, they even tell you not to on the box). If youinsist: "Don't use fluoride toothpaste, since it sticks to teeth and blocks peroxide from getting in," says Michael Apa, a dentist in New York City. Instead, get that minty freshness with an all-natural, fluoride-free toothpaste. You should, however, floss before whitening. It dislodges plaque, which also prevents bleach from penetrating.

3. You bleach right before a boozy party. You've got some downtime before a boozy wine-and-grub party, so it's the perfect time to slap on a whitening strip, right? Wrong: "Be careful with wine, coffee, tea, and berries while you're whitening, since peroxide makes teeth more porous and prone to stains for 72 hours," says Kevin B. Sands, a dentist in Los Angeles. And while we're at it, you're not entirely in the clear drinking white wine, either. It's super-acidic and removes a microlayer of your teeth, making them more susceptible to staining. The best move? Chase each glass of wine with a glass of water, and only whiten when you know you can avoid potential stains for a few days.

Find more teeth-whitening tricks in our September issue, on newsstands August 26.

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