Food Reinforcement, Weight Status, and Energy Density

Study Overview
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Brief Summary
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The investigators previous studies have shown that obese and non-obese individuals respond differently to daily intake of snack food. The purpose of this study was to determine whether these differences are specific to high energy density snack foods. The investigators hypothesized that obese individuals would show an increase in motivation to obtain high energy density snack foods after two weeks of daily consumption, but that non-obese women and obese women consuming low energy density foods would have reduced motivation to consume snack foods after two weeks of daily consumption.

Official Title
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Effects of Daily Snack Food Intake on Food Reinforcement Depend on Weight Status and Energy Density

Conditions
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Reinforcing Value of Food

Intervention / Treatment
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* Behavioral: Daily snack food intake


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: 18 - 50 years old, female, like study foods. Exclusion Criteria: current smoker, currently on a diet, medical conditions or medication affecting appetite (ex. methylphenidate).

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 50 Years

Sexes Eligible for Study
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Female

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

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Non-obese/HED<br>Non-obese women given 60 gram portions of high energy density snack foods to consume daily for two weeks. | Behavioral: Daily snack food intake<br>* participants consumed 60 gram portions of either low energy density or high energy density snack foods every day for two weeks.<br>|
| Non-Obese/LED<br>Non-obese participants that were given 60 gram portions of low energy density foods to consume daily for two weeks. | Behavioral: Daily snack food intake<br>* participants consumed 60 gram portions of either low energy density or high energy density snack foods every day for two weeks.<br>|
| Obese/LED<br>Obese participants that were given 60 gram portions of low energy density snack foods to consume daily for two weeks. | Behavioral: Daily snack food intake<br>* participants consumed 60 gram portions of either low energy density or high energy density snack foods every day for two weeks.<br>|
| Obese/HED<br>Obese participants that were given 60 gram portions of high energy density snack foods to consume daily for two weeks. | Behavioral: Daily snack food intake<br>* participants consumed 60 gram portions of either low energy density or high energy density snack foods every day for two weeks.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of operant responses | Participants were asked to click a mouse button to gain access to food. A point was earned after a certain number of button presses and after 5 points were earned, the participant received 100 kcal portion of food. | about one month | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Food liking | participants rated how much they liked the food on a Likert-type scale. | about one month | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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food reinforcement, food liking, motivation, dopamine, obesity, energy density, snacks