Chewing, Eating Rate, and Weight Status in Children

Objectives Primary Objective: To examine whether there is an association between theeating duration of a standard meal and weight status (as BMI Z‐score) among children aged6‐11.Secondary Objectives: 1. To determine whether there is an association between the number of chews of astandard meal and the weight status of children aged 6‐11. 2. To examine whether there is an association between chewing rate (total weight offood consumed/total eating time) during a standard meal and daily energy intakeamong children. 3. To examine whether there is an association between chewing rate during a standardmeal and body composition among children. 4. To examine whether there is an association between the eating duration of a standardmeal and the reported satiety level of children aged 6‐11. 5. To examine whether there is an association between the eating duration of a standardmeal and total daily energy intake. 6. To assess whether the associations between chewing behaviors, eatingcharacteristics, and dietary intake differ between boys and girls. 7. To assess the relationship between chewing‐related behaviors and salivary ghrelinresponses before and after meal consumption.Study Design and Methodology Study Design: This doctoral project is a randomized,crossover, laboratory‐based experimental study conducted among healthy children aged 6‐11years. Participants will attend multiple assessment sessions during which they willconsume standardized isocaloric test meals differing only in food texture and chewabilitycharacteristics. The crossover design enables within‐subject comparison of oralprocessing responses under different meal conditions while reducing inter‐individualvariability. All experimental sessions will be conducted under standardized laboratoryconditions.Study Population: The study will include approximately 70 children aged 6‐11 years,including those with normal weight and those with obesity, according to World HealthOrganization BMI‐for‐age z‐score criteria. Children with medical conditions or dietaryrestrictions that may affect eating behavior, appetite regulation, or food consumptionwill be excluded. The selected age range represents a critical developmental stage duringwhich eating patterns, satiety regulation, and obesity‐related behaviors may still beinfluenced through behavioral and nutritional interventions.Primary Outcomes: Primary oral processing variables will include: Chewing duration;Number of chews; Eating duration; Eating rate; Amount of food consumed.Secondary Outcomes:1. Satiety Assessment: Subjective hunger and satiety responses will be evaluated usingvalidated Visual Analog Scale (VAS) ratings before the meal, immediately after the meal,and during the postprandial period.Hormonal Assessment: Salivary ghrelin concentrations will be measured before and aftertest meals using standardized saliva collection and biochemical analysis procedures.Ghrelin was selected due to its established role in appetite regulation and meal‐relatedhunger signaling.Methods Study Procedure: Participants will consume standardized test meals developed todiffer in texture and chewability while maintaining comparable caloric and macronutrientcomposition. Meals will include foods categorized according to oral processing difficultyand chewing demands. During meal consumption, oral processing behaviors will beobjectively assessed using synchronized behavioral and physiological measurement systems.To account for familial and shared environmental influences on eating behavior, at leastone parent will undergo a parallel assessment, conducted separately from theparticipating child.Meal consumption will be recorded using panoramic video cameras, and chewing‐relatedbehaviors will be coded by independent evaluators. In addition, meals will beadministered using the Universal Eating Monitor (UEM), a concealed scale‐based systemthat continuously records food intake throughout the meal and enables high‐resolutionassessment of eating microstructure.Anthropometric and Body Composition Assessment: Children and parents will undergostandardized measurements of: Weight and height; BMI‐for‐age z‐score/Parental BMI; Bodycomposition using InBody 770; Upper‐body muscle strength using JAMAR dynamometry.Dietary and Behavioral Questionnaires: Additional assessments will include: 24‐hourdietary recalls; Physical activity questionnaires; Sociodemographic questionnaire;Children's Eating Behavior Questionnaire (CEBQ) (children only); AUT‐EAT questionnaire(to assess eating behaviors and challenges specifically in children on the AutismSpectrum) (children only); parental eating behaviors questionnaire. Parents weight,height and eating behaviors will be recorded during one meal session.Statistical Analysis: Statistical analyses will be conducted using IBM SPSS Statistics,version 31.0. Descriptive statistics will summarize participant characteristics overalland by weight‐status group. Continuous variables will be assessed for normality andpresented as means ± SD or medians and interquartile ranges, as appropriate; categoricalvariables will be presented as frequencies and percentages. Group comparisons will beperformed using t tests, Mann‐Whitney U tests, chi‐square tests, or Fisher's exact tests,as appropriate.Given the randomized crossover design, primary analyses will use linear mixed‐effectsmodels to account for repeated measurements within participants across meal conditions.Models will include participant as a random effect and meal texture, weight status orBMI‐for‐age z‐score, visit order, and relevant covariates, including age, sex, andsocioeconomic characteristics, as fixed effects. Interaction terms will be used toexamine whether responses to soft versus hard meals differ by weight status or sex.Primary behavioral outcomes, including eating duration, chewing duration, number ofchews, eating rate, and food consumed, will be analyzed in relation to BMI‐for‐agez‐score, body composition, satiety ratings, ghrelin responses, and total daily energyintake. Satiety and salivary ghrelin changes will be examined using repeated‐measuresmodels and pre‐to‐post meal change scores. Parent‐child associations in eating behaviorsand anthropometric measures will be explored using correlation and regression analyses.Exploratory mediation analyses will assess whether satiety and ghrelin responsespartially explain associations between oral processing behaviors and weight‐relatedoutcomes. Model assumptions will be evaluated, and sensitivity analyses will be conductedfor missing or extreme values. Statistical significance will be set at p < 0.05, witheffect sizes and 95% confidence intervals reported alongside p values.