If you think you're doing your teeth a favor by sipping white wine instead of red, you may need to rethink your tooth-whitening strategy.
A new study shows that white wine has an acid content that could increase dark dental stains.
A new study shows that white wine has an acid content that tends to increase the risk of dark dental stains if you also drink tea or similar beverages.
New York University researchers compared the staining effects of red and white wine by submerging cow teeth in wine for one hour -- the same effect as sipping a couple of glasses of wine over the course of a leisurely dinner.
Why cow teeth? Their surface is similar to human teeth, said Dr. Mark Wolff, a professor and chairman of the department of cariology and comprehensive care at NYU's College of Dentistry. The researchers then soaked the teeth in black tea, in an effort to mimic the same exposure you'd get from drinking several cups of tea.
Compared to water, the acidity of the white wine left teeth more susceptible to the tea stains. While white wine was still better than red wine in terms of subsequent tooth staining, if you drink any shade of vino you seem to be more vulnerable to staining by so-called chromogens -- substances in tea and other food that discolor teeth. Health.com: Whiten your teeth the natural way
"I used to give out this voodoo advice that patients should drink white wine, not red," said Wolff, who was scheduled to present the study Wednesday at the International Association for Dental Research meeting in Miami, Florida. "But I was wrong."
When combined with the beverage's acidity, the tannins in white wine act as a binding protein and help chromogens to saturate the tooth's surface, said Wolff. So when you linger over a cup of tea at the end of dinner, you are inadvertently discoloring your teeth. Health.com: The healing power of tea
"Every time you do this, you increase the amount of stains on your teeth," he said.
And although the researchers didn't look at coffee, java drinkers might see some staining as well. In general, though, coffee doesn't stain teeth as much as tea. "The intensity of the chromogen is less," said Wolff.
Wolff said you don't need to switch beverages just yet. It's not the white wine itself that stains, it's what you eat and drink while consuming it that counts.
"If you're consuming white wine, white grapes, and cheese, you aren't going to see any staining," he said. Health.com: Inexpensive natural wines that we love
However, brushing your teeth right after a sipping a crisp Chardonnay may actually make the problem worse. Brushing immediately after consuming a very acidic beverage may damage the tooth's structure, said Wolff, so it's better to wait for a bit.
"Saliva has the capability of re-mineralizing the tooth structure and neutralizing damage," he said. "So give it 40 minutes to an hour before you brush your teeth."
Still, some experts aren't convinced. "When you take a sip of wine, your front teeth probably aren't even touching it," said Dr. Richard Price, a spokesperson for the American Dental Association. "That's very different than submerging your teeth in wine, so I don't know what the relevance to real life is here."
And if saliva acts as a neutralizer over time, naysayers of the study claim that it would act as a buffering agent over the course of the meal, so winding down with a cup of tea shouldn't leave you with a dingy grin.
"I'm not going to give up my Pinot Grigio," said Price, "and I wouldn't tell my patients to either." Health.com: Cocktail confidential-- How many calories are really in your favorite drinks?
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