An examination of research on oral health, commissioned by the World Health Organisation found that whole grain carbohydrates help improve oral health.

Although the researchers found no association between the total amount of starch eaten and tooth decay, they did find that more processed forms of starch increased the risk of cavities. This is because they can be broken down into sugars in the mouth, by amylase found in saliva.

Further findings, although based on very few available studies and weaker data, suggested a lower risk of oral cancer from consuming whole grain starches, and that whole grains may also offer protection against gum disease. Lead researcher Paula Moynihan, said, "The evidence suggests that a diet rich in whole grain carbohydrates is less likely to damage your oral health than one containing processed starches."

In the review, 33 papers were included of studies on foods containing what were characterized as rapidly digestible starches (e.g. white bread, crackers, biscuits, cakes, pretzels) and slowly digestible starches (e.g. whole grains, legumes), and their relationships with dental caries, oral cancer and gum (periodontal) disease. The full findings are present in the journal- Journal of Dental Research.