Brain Responses to Visual Food Cues in Response to a Low Carbohydrate Diet

Study Overview
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Brief Summary
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The aim is to profile and elucidate the hormonal and neurological system interaction to food related behavior. The stimulus used will include visual and taste (gustatory) stimuli. The study will profile induced correlations of metabolic parameters, gut hormones and brain region (ROI - regions of interest) activation and interaction. In this study we will use fMRI (functional MRI) to compare brain responses in obese, normal-weight and reduced weight subjects. The food stimuli will be blocked into specific categories to allow for investigation of different responses to alternating energy density foods. The response will be tested prior to and following a brief low carbohydrate dietary regimen.

Detailed Description
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The study will be a longitudinal study where the participants will come back twice on the same phase of the period- both visits in the luteal phase with a month between each visit. In this part of the study there will be 40 participants with a wider range of BMI. This phase of the study will include a nutritional intervention - the participants will be asked to have a carbohydrate restricted diet (60 grams of carbohydrate)- for a period of a month with no caloric restriction. Food records will be kept and followed and a ketone test (blood test) will be done on the morning of the study visits.

Official Title
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Brain Responses to Visual Food Cues in Response to a Low Carbohydrate Diet

Conditions
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Changes in Functional MRI

Intervention / Treatment
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* Other: low carbohydrate consumption


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18- 45 years No contraindication to enter the MRI No significant visual problems that may hamper visualization of visual stimuli within the magnet No contraceptive hormonal replacement relatively regular menstrual cycle Exclusion Criteria: contraceptive hormonal replacement under the age of 18 over the age of 45 pharmacological treatment that can effect brain response Irregular menstrual cycle

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 45 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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Design Details

Primary Purpose: Basic Science
Intervention Model: Sequential Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Low carbohydrate consumption<br>consumption of up to 60 grams of carbohydrate a day for 10 days FMRI will be performed prior and after the intervention during the luteal cycle phase | Other: low carbohydrate consumption<br>* consumption of up to 60 grams of carbohydrate a day for 10 days FMRI will be performed prior and after the intervention during the luteal cycle phase<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| fMRI:(Functional MRI) changes in activation patterns of reward associated regions will be assessed prior and after dietary intervention | BOLD (Blood Oxygen Level Dependent) responses will we quantified in regions of interest | fMRI will be preformed in the luteal menstrual phase at two time points (at least a month apart). a comparison will be made between pre and post intervention. |