CENTER CITY (WPVI) -- America's love affair with soda is falling flat, in favor of seltzer or sparkling waters.
However, a Philadelphia dentist urges seltzer-lovers not to go overboard. Those beverages have some downsides, too.
Rehan Mirza used to enjoy seltzer all day at his desk.
"It was something I used to sip on while I'm taking meetings, I'm on a call, you know, doing my work," said Mirza.
He thought it was the healthiest thing he could drink - an alternative to the sugar from colas.
But six months ago, his teeth began bothering him.
"I started feeling sensitivity to, you know, coffee, cold water," he said
That sent him to dentist Dr. Shireen Malik of Nicholas Cosmetic Dental.
Dr. Malik says sensitive teeth is a common complaint among her patients. Many drink lots of seltzer.
"You think you're doing yourself a favor, but you're really not," said Dr. Malik.
That's because of the pH levels of carbonated water.
Pure water has a pH of about 7. Plain, room temperature sparkling water is about 3 to 4 - slightly acidic.
Flavors like lemon or grapefruit can take that down to 2 and a half or 3 - highly acidic.
"That acid is dissolving the enamel, and that's making their teeth weaker," said Dr. Malik. "Once the enamel is gone, it's gone."
Enamel-building toothpastes can help with slight damage, but not serious levels.
Dr. Malik and the American Dental Association suggests seltzer-lovers dial back consumption.
"Maybe have it once a day, at one time with food, because then it's diluted a little bit. And then have it at room temperature," she said.
Or, drink regular water. Dr. Malik says there's no substitute for it.
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