Key points

Introduction

Acid produced during bacterial fermentation of dietary carbohydrates dissolves enamel and/or dentin, leading to dental caries. Thus, caries is a diet-related disease. Although attention typically focuses on fermentable carbohydrates, specifically sugars, fermentable carbohydrates are not consumed in isolation. Carbohydrates are nutrients within foods and beverages. Individual foods and beverages contain a myriad of differing nutrients in varying concentrations, and ultimately food and beverage choices and eating behaviors are associated with the caries process. Consideration of food and beverage choices and eating behaviors is necessary for effective caries prevention. This article defines a healthy diet and eating behaviors as a foundation for caries prevention; identifies food and beverage choices and eating behaviors associated with caries; identifies diet-related screening and assessment tools for caries risk; and provides counseling strategies for patients at risk for dental caries.

Diet

The term “diet” is simply defined as the foods and beverages one typically consumes. Foods and beverages deliver nutrients, which are defined as substances necessary for growth, maintenance, and/or repair of body tissues. Nutrients providing energy include proteins, fats, and carbohydrates. The terms “nutrient dense” and “energy dense” are used to describe the relative concentrations of nutrients and energy within individual foods and beverages. In addition to caries, the choice of foods and beverages consumed, balanced by their nutrient and energy densities, influences systemic health and chronic disease.

Dietary guidelines, including the United States Dietary Guidelines (USDG), offer recommendations for health promotion and disease prevention. The overall objectives of dietary guidelines are to identify nutrients necessary for growth, maintenance, and repair; to recommend the types and amounts of foods to provide necessary nutrients; and to identify non-nutrient compounds or foods to limit for prevention of chronic disease. Recommended nutrient intakes are defined by age and gender in the Dietary Reference Intakes (DRIs). Ideally, individuals choose nutrient-dense foods to meet their individual nutrient requirements within their energy requirements. Nutrients within foods are more bioavailable than nutrients from supplements; notable exceptions include vitamins B ₁₂ and folate.

A healthy diet will limit exposure to excessive nutrient intakes, non-nutrient compounds associated with chronic disease (ie, added sugars, cholesterol), and environmental contaminates that might include lead, bacteria (ie, Salmonella ), natural toxicants (ie, solanin), or pesticide exposures. The Tolerable Upper Intake Level within the DRIs identifies the maximum amount of a nutrient that is considered safe for most healthy individuals and beyond which there is an increased risk of adverse health effects by age and gender. The USDG and the World Health Organization (WHO), respectively, recommend that intake of both added and free sugars be limited to less than 10% of total energy intake (ie, 12 teaspoons/2000 kcal) for oral and systemic health, with the WHO suggesting that 5% (ie, 6 teaspoons/2000 kcal) might be more appropriate for caries prevention. Added sugars are defined as sugars used as ingredients and added during food processing, home preparation, or at the time of consumption, whereas free sugars are defined as sugars added to foods by the manufacturer, cook, or consumer or naturally present in honey, syrups, fruit juices, and fruit concentrates. Inclusion of added sugar content on food labels is designed to help consumers make healthier food choices. In 2016, the United States Food and Drug Administration announced that grams of added sugars would be included on food labels beginning in 2018; implementation has been delayed until January 2020 for manufacturers with $10 million in food sales.

Dietary guidelines throughout the world support consumption of minimally processed foods, particularly those readily available and accessible to the consumer. Minimally processed foods may have been cleaned, cooked, or preserved, and their origin is easily recognized. By contrast, ultraprocessed foods are made from transformed food ingredients with little semblance to their original foodstuff (ie, chocolate, chips, hotdogs). As the food commodity moves along the processing continuum, nutrient density decreases while energy density increases. The USDG generally recommends consumption of minimally processed foods, recognizing that limited quantities of ultraprocessed foods may be consumed within a healthy diet. ChooseMyPlate is an online program that translates the USDG to consumer food recommendations, and presents food group plans by age and gender for healthy Americans. Table 1 provides examples of ChooseMyPlate plans for males and females aged 4 to 8, 14 to 18, and 31 to 50 years, and is available at https://www.choosemyplate.gov/MyPlate .

The USDG and ChooseMyPlate are evidence based, and the science defining a healthy diet is clear. In reality, one’s food choices are heavily influenced by multiple factors and not necessarily consistent with a healthy diet. The Social-Ecological Model is a visual framework that identifies individual, setting, sector, and social or cultural factors that influence food and activity decisions. From a pragmatic perspective, transportation, finances, and living conditions heavily influence access to and availability of healthy food. Compliance with the USDG depends on a supportive environment; individuals of lower socioeconomic status often lack transportation to access the resources to purchase, and household facilities to safely store and prepare minimally processed foods.

Eating behaviors

Eating behaviors or habits refer to the when, where, and how foods and beverages are consumed. Although eating behaviors are known to influence food choices and systemic health, the science associating eating behaviors with caries risk is more advanced. In essence, eating behaviors that increase either the frequency or length of carbohydrate consumption will consequently increase the exposure time (ie, the opportunity for oral bacteria to ferment the carbohydrate), and thus increase the risk of caries.

The ideal eating behaviors match food and beverage intake to appropriate hunger cues. A mismatch between eating and hunger leading to prolonged or excessive hunger increases the risk of binge eating upon food or beverage presentation, and eating without hunger increases the likelihood of snacking on highly palatable, ultraprocessed foods or beverages at the expense of minimally processed foods. Thus, healthy eating behaviors emphasize structured eating and include 3 meals and 2 to 3 snacks per day. All energy-containing foods and beverages should be consumed within these structured eating events.

Young children have proportionately higher energy requirements than adults and smaller stomach capacities. For young children to consume adequate energy and nutrients, more frequent eating events are required. In addition, regular access to meals and snacks at appropriate intervals during early childhood is associated with food security and a healthy relationship with food. In adults, systemic conditions that alter stomach capacity and/or satiety responses might also affect the frequency of eating events.

Dietary recommendations for caries prevention should be consistent with age-appropriate eating behaviors and should consider systemic modifiers. From birth through 6 months of age, human milk and/or infant formula should be provided on demand in response to infant hunger cues. At approximately 6 months of age, texture-appropriate solid foods and meal structure should be introduced. By 1 year of age, all energy-containing foods and beverages should be provided at 3 meals and 2 to 3 snacks. The ubiquitous availability of foods and beverages within contemporary environments is associated with a decrease in structured eating events. Grazing or prolonged snacking on foods and/or beverages is commonplace. Unfortunately, the prolonged consumption of foods and/or beverages containing added sugars increases the opportunity for their fermentation within the oral cavity and subsequent caries risk.

Cultural customs that encourage or support the use of foods and/or beverages to address emotional needs can result in prolonged fermentable carbohydrate exposures that increase the risk of caries. Provision of minimally processed foods and/or beverages at gatherings to celebrate religious, cultural, or life events is a foundation of and central to many westernized celebrations. Indeed, children and adolescents raised in families sharing 3 or more meals per week are less likely to be overweight and more likely to eat healthy foods than peers sharing less than 3 meals. However, the use of ultraprocessed foods and/or beverages to reward behaviors, heal wounds, or soften losses can lead to unhealthy relationships with foods, which can lead to emotional eating—that is, using food to address emotional needs instead of using more appropriate means of dealing with emotions. Emotional eating is associated with unhealthy food choices and prolonged eating, both of which can increase the risk of dental caries.