Lately, people have been buying into all sorts of home fixes to whiten, brighten, and even straighten your smile, and those "hacks" end up all over Pinterest. But do they really work? Cosmopolitan.com asked Kevin Sands (a Beverly Hills dentist who works on the pearly whites of the Kardashian-Wests, Justin Bieber, Miley Cyrus, and pretty much every celeb you can think of) whether or not these hacks are safe to try and if they'll actually work. Here's his expert opinion:

1. Rub the inside of a banana peel onto your teeth for two minutes to whiten them.

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Lauren Ahn

The worst-case scenario here is that nothing happens and you just look like a monkey. "There are amazing minerals in banana peels like potassium, magnesium, and manganese that can absorb into your teeth and whiten them," Dr. Sands confirmed. "But after I did some research and had people try out this procedure, it doesn't seem to work very well. Maybe just a subtle difference." 

2. For white teeth, mix 3 teaspoons baking soda with 2 teaspoons lemon juice. Rub a cotton swab over teeth. After 30 seconds, rinse and brush. 

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"This can be dangerous. Baking soda is abrasive and lemon juice is highly acidic. The combo can be erosive to the enamel (aka the outer tooth coating)," Dr. Sands warned. So basically this can break down the outer layer of your teeth? Pass please!

3. Fill a mouthguard with hydrogen peroxide and baking soda, then use it for 20 minutes a day for two weeks to get a whiter smile. 

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Lauren Ahn

Good news! "Diluted hydrogen peroxide can have a whitening effect and be safe," said Dr. Sands. "If placed in the mouth with baking soda in a night guard, it won't be too abrasive, so there's no harm in trying." But he did note that the results won't be as dramatic as a professional treatment. 

4. Mix baking soda and a drop of water to make a paste. Apply for 10 minutes and get an instantly whiter smile.

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Lauren Ahn

There's pretty much no point to this one. "Baking soda can be abrasive if brushed harshly against enamel, but if just placed on the teeth without vigorous brushing it won't harm anything, but wont bleach the teeth either," explained Dr. Sands.

5. Make a homemade mouth wash using cinnamon.

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Getty | Lauren Ahn

"While this combination of cinnamon, honey, and lemon sounds delicious, it would not be a good idea to use this as a daily mouth wash. Lemon juice is very acidic and can be erosive to enamel, and honey has a very high sugar content that can cause dental decay if coating the mouth daily," Dr. Sands explained. Mouthwash aside, anyone else wondering how this mix tastes with vodka?! 

6. DIY a toothpaste using coconut oil and baking soda.

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"This pin suggests mixing coconut oil, baking soda, and essential oils. Baking soda is much too abrasive to be brushed against the enamel," explained Dr. Sands. "And this homemade 'toothpaste' doesn't have any fluoride, which is the key ingredient in toothpaste for preventing dental decay."

The moral of the story here: If a pinned hack sounds too good (or too crazy) to be true, it probably is. When in doubt, just call Kimye's dentist. Although yours will probably be able to help too. 

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