Cheesy plaque attack.

Cheesy plaque attack 

Four years ago, Mark Jensen, director of clinical studies at the University of Iowa dental school in Iowa City, noticed that aged-cheddar, Swiss and Monterey Jack cheeses help fight tooth decay. Although the mechanism of action remains unknown, he and his co-workers have now confirmed that another nine cheeses--Edam, Gouda, Muenster, mozzarella, Port Salut, Roquefort, Romano, Stilton and Tilsit -- perform equally well in limiting tooth decay.

Ordinarily, when carbohydrates such as sugar become trapped in plaque--the film on tooth surfaces that incubates cavity-fostering bacteria -- they are converted to tooth-destroying acids. But in a week-long study, electrodes implanted between the teeth in five volunteers recorded no significant increase in the acidity of plaque when a sucrose (table sugar) tooth rinse followed the subjects' consumption of any of the 12 cheeses. However, plaque acidity increased 1,000-fold--to a pH of 4--when the sugar rinses were not preceded by a cheese snack. In a related experiment involving only cheddar, Jensen found that consumption of this cheese four times daily for two weeks caused a 20 percent remineralization (tooth-surface rebuilding) in synthetic tooth-like materials temporarily attached to root areas and 5 to 10 percent remineralization in materials similar to tooth-crown enamel.

These studies suggest that the 12 tested cheeses, when eaten as snacks, are as benign as sugarless gu--at least in terms of cavity formation, Jensen says. And when eaten--or just chewed without swallowing--before a sweet meal, he adds, they might limit tooth decay by preventing the formation of tooth-demineralizing acids.