Soda Soak In case your soda habit survived last week's findings that tied regular doses of sugary soft drinks to rapid weight gain and diabetes, there's more bad news: Another just-published study suggests the bubbly stuff isn't so good for your teeth, either. Researchers from the dental school at the University of Maryland, Baltimore, compared the enamel-eating properties of 16 different drinks -- including 12 soft drinks -- after immersing bits of teeth in them for two weeks. Study results were published in the journal General Dentistry.

Do the Dew? Among the fizzy drinks, non-colas tended to be harshest on teeth; diet versions were no better than their sugary counterparts. The most corrosive was Mountain Dew; the diet version dissolved just over an average 8 percent of enamel; the regular version ate away more than 6 percent. Sprite and Diet Sprite followed at 3.93 percent and 3.65 percent, respectively. Coffee and brewed tea had only minimal effects.

Fixing Blame The researchers, Anthony von Fraunhofer of Maryland and Matthew Rogers, now an Air Force dentist, found no connection between sugar content and enamel dissolution. (A&W Root Beer had no effect on teeth, despite a generous dose of sugar.) Nor did pH level seem linked to enamel loss. The researchers speculate that other ingredients such as citric or malic acid may be responsible.

Wishful Swishing? The National Soft Drink Association dismissed the findings, saying that in real life teeth receive nothing like the 14-day immersion. Beverages are in contact with the teeth for only moments, said Richard Adamson, the trade group's vice president for scientific and technical affairs, who said protective forces like saliva further blunt the effect of the drinks. But Rogers and von Fraunhofer called the effect of the 14-day immersion similar to what regular soda drinkers would see over 13 years of daily consumption.

-- Brian Reid