Aspartame and dental caries in the rat

Aspartame (NutraSweet--The NutraSweet Co., Deerfield, IL) an artificial intense sweetener, was tested for its cariogenicity alone and in the presence of sucrose. Sprague-Dawley rat pups (Charles River Laboratories, Bloomington, MA) inoculated with Streptococcus mutans were fed basal diet 2000 with one of the following added: 50% sucrose; 30% sucrose; 30% sucrose + 0.15% aspartame; 0.30% aspartame; 0.15% aspartame and no addition. The animals were sacrificed after eight weeks. Caries was evaluated using Keyes' technique. It was found that the addition of 0.15% aspartame to 30% sucrose diet significantly reduced caries in comparison to rats fed only 30% sucrose diet. In animals fed aspartame only, there was no caries. The S. mutans counts were high in the animals receiving sucrose diets with and without aspartame. The animals receiving only aspartame had very low S. mutans counts.