Frequent, lengthy exposure to acid attacks can result in decay. The acid also 'nibbles away' at bits and pieces of food left between the teeth or along the gum line. Over time, the food particles break down, resulting in more sticky plaque and more bacteria. Each sugar encounter sets off an 'acid attack'. The more frequent the snacking, the more frequent the number of 'acid attacks'.
Sweets are less harmful when eaten in conjunction with a meal.
The best advice is to avoid all-day snacking or continually sipping on sweetened liquids, including diet sodas. Any hard candy which stays in the mouth a long time, results in longer acid attacks on tooth enamel. In adults, cavities typically form along the gum line and the edges of old fillings. That's because our gums recede with age, often the result of gum disease, medication use, or years of aggressive brushing. Receeding gums expose the tooth root.