Association between food difficulty and oral function in school-aged children

Objective: This study aimed to investigate the relationship between children's subjective perception of food difficulty and the physical properties of foods, and to examine how these factors are associated with oral function development. Methods: A questionnaire survey on “food difficulty” was conducted on 25 types of foods with 133 first-grade elementary school students (70 boys and 63 girls). The physical properties of the foods (hardness, cohesiveness, and adhesiveness) were measured. The masticatory difficulty score for each child was calculated by integrating texture values with their subjective evaluations. In addition, oral function measurements were conducted, including occlusal force, lip-closing strength, tongue pressure, masticatory performance, and masticatory path width. Associations between masticatory difficulty scores and oral function were analyzed using Spearman's rank correlation. Results: Foods with higher hardness and cohesiveness were rated as more difficult to eat. Children who perceived hard and cohesive foods as difficult to eat tended to exhibit a lower occlusal force and reduced masticatory performance, suggesting an underdeveloped masticatory function. However, the association with adhesiveness was limited, indicating the potential influence of non-physical factors such as preference or food shape. Conclusion: Children's subjective perception of food difficulty is closely related to food texture, particularly hardness and cohesiveness, and is associated with oral function development. These findings suggest that incorporating food texture into oral health assessment and dietary education is a beneficial approach, as it may help foster eating habits that promote the development of masticatory function in children.