Frequency of carbohydrate intake

The most significant patient behaviour factor leading to an increase in caries risk is the frequency of consumption of fermentable carbohydrate. There is good evidence that it is the frequency of eating rather than the total quantity of fermentable carbohydrate consumed that causes caries. The mono and disaccharides are the most vulnerable to rapid fermentation, though some of the highly processed starches have also been shown to contribute to acid production. The acids resulting from carbohydrate fermentation are weak organic acids and in most cases will only cause chronic low grade demineralisation. However, when a high frequency of sugar consumption is maintained over a prolonged period, or there is a serious deficiency of natural host protective factors, caries will progress more rapidly. This is best demonstrated by the Stephan Curve as shown in the illustration below -

A drop in pH in plaque after a glucose rinse

(adapted from Nikiforuk 1985)

See Book page 75, Figure 6.20 for full diagram