For those of us with a sweet tooth, there is good news on the dental front. Despite the fact that raisins are sweet and sticky, scientists at the University of Illinois in Chicago have found them to contain compounds that prevent tooth decay and gingivitis.
There are a number of constituents in raisins that address the problem of plaque-causing bacteria in the mouth. Some, like oleanolic acid are very good at killing these bacteria. Oleanolic acid, oleanolic aldehyde, and 5-(hydroxy methyl)-2-furfural also reduce the ability of these bacteria to grow. In particular, they work against Streptococcus mutans, and Porphyromonas gingivalis.
Oleanolic acid is also effective at preventing the bacteria Streptococcus mutans from sticking to the surface of the tooth, The bacteria need to stick to the teeth to form plaque, after which they start eroding the tooth enamel. Sucrose, not the fructose and glucose that raisins have in them, are what creates the environment for tooth decay.
Cranberries have also been found to prevent bacteria (specifically Streptococcus mutans) from sticking to teeth, and causing gum disease and tooth decay. There are now dental floss products and toothpastes in the US that contain cranberry extract. And the British Dental Health Foundation is recommending cranberry extracts and juice to prevent tooth decay and associated problems. But because of cranberry juice's acidity, they recommend only taking it at mealtimes. Acidic food and drinks temporarily soften the enamel on teeth.
Symptoms of gum disease include red and swollen gums that bleed easily, tooth sensitivity, spaces developing between teeth, pus between teeth, chronic bad breath, pain in the mouth, and changes to the bite of teeth. Plaque is the main cause of gum disease, though other factors can speed up the process of gum degradation. These include smoking, a genetic predisposition, pregnancy, puberty, stress, poor diet (and yo-yo dieting wouldn't help), medications like anti-depressants, and oral contraceptives, grinding teeth at night, diabetes, and some other systemic diseases.
References:
1. www.perio.org
2. www.nutraingredients.com/news/ng.asp?id=60518
3. www.nutraingredients.com/news/ng.asp?id=567