Study of Nutrition and Activity in Kids

Study Overview
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Brief Summary
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While a substantial body of research suggests that RRV is related to obesity, there is very little research on factors that contribute to the RRV of food, particularly how patterns of eating can increase or decrease the motivation to eat specific foods. Previous work has demonstrated that a subset of individuals with obesity show increases in RRV of food after repeated consumption of large portions of high energy density (HED) snack foods, which has been conceptualized as sensitization. Preliminary data suggest that sensitization of the RRV of HED food is a predictor of weight gain over time. However, more work needs to be done to address this relationship using a planned, prospective study design, using adolescent research subjects, and examining potential moderators of this relationship. The purpose of this study is to identify risk and protective factors to excess zBMI change in adolescents over time. Aim 1 was to measure the relative reinforcing value (RRV) of a preferred HED and low energy density (LED) snack food before and after 2-weeks of daily exposure. Aim 2 was to assess the RRV of exercise and sedentary activity. Hypotheses include 1) sensitization to HED food will be associated with greater zBMI at the time of testing as well as greater zBMI change over time 2) sensitization to LED food will be associated with lower zBMI at the time of testing in adolescents and less zBMI change over time. 3) Greater RRV of exercise will be protective against zBMI increases over time.

Official Title
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Sensitization of the Reinforcing Value of Food as a Predictor of Weight Change in Adolescents

Conditions
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Obesity, Adolescent, Adolescent Behavior

Intervention / Treatment
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* Other: Reinforcing value of HED and LED foods in response to snack food monotony


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: between 12-14yoa (male and female) zBMI: -1.5 to +2.0 (*determined by Height/weight measurement at Visit 1) neutral or higher liking of the study foods Willingness to complete 9 study visits over 2 years. Exclusion Criteria: -metabolic or endocrine disorder use of medications known to effect appetite (Ritalin, Adderall, Concerta, Wellbutrin, Prednisone, etc) Unwilling to complete the study visits allergy to study foods dislike of study foods (*determined via Preference for Study foods forms at Visit 1) parent report that child reads below 4th grade reading level parent report that child cannot complete light physical activity without assistance No English Speaking parent or legal guardian (therefore cannot provide consent in English nor answer questionnaires for this study) * all other exclusion criteria are assessed from Survey monkey screening in advance of the first appointment vis parental report. At the first appointment the child is directly asses for height, weight, and The linking of study foods.

Ages Eligible for Study
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Minimum Age: 12 Years
Maximum Age: 14 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Other: Reinforcing value of HED and LED foods in response to snack food monotony|Each child will be asked to eat two different snack foods over the course of two weeks each. The RRV of that food (vs alternative reinforcer) will be tested and baseline and post exposure. Increases in RRv for food after monotony will be considered sensitization to that food. All children will be followed to observe weight change over time for 2 years each.|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| zBMI Change | BMI z-score change over time. zBMI is a standardized index of body mass index used in children that is standardized to age and sex specific measurements from a national sample. 0 represents the national average. A positive number reflects a body mass index that is higher than the national average and a negative number reflects a body mass index that is lower than the national average. | through study completion, an average of 24 months from baseline. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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adolescent, obesity, relative reinforcing value, physical activity, weight change