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The Role of Altered Nutrient Partitioning in Food Reward

Not Applicable
Completed
Conditions
Overweight and Obesity
Interventions
Other: High-Fat Test Meal Inside a Metabolic Chamber
Other: High-Carbohydrate Test Meal Inside a Metabolic Chamber
Registration Number
NCT05200845
Lead Sponsor
Virginia Polytechnic Institute and State University
Brief Summary

Obesity remains a public health epidemic despite substantial advances in treatment strategies and therapies in the last decade. Effective strategies to support maintenance of improved metabolic health and reduced body weight are still needed.

Signals from the gut to the brain are important in regulating metabolism and energy balance and have been linked with food reward and preference in metabolically healthy individuals with normal body mass index. In particular, post-ingestive signaling related to glucose metabolism has been linked with food reward and preference. However, not much is known about how these gut and brain signals interact to influence eating behaviors in states of obesity or altered metabolic health. In addition, evidence in rodent models and human studies indicates obesity is associated with a blunted brain response to foods compared with normal body weight. However, whether altered nutrient utilization, termed metabolic inflexibility, influences the relationship between obesity and food reward has yet to be studied.

The overall objective of this proof-of-concept pilot study is to assess the feasibility of measuring reward response following a flavor-nutrient conditioning paradigm across the normal to obese body mass index (BMI) range and in states of altered metabolic health. The aims of this study are: 1) to determine whether differences in reinforcement learning/flavor-nutrient conditioning of carbohydrate can be measured across the body mass index range; and 2) to determine the feasibility of assessing metabolic flexibility and whether a relationship between metabolic flexibility and calorie-predictive reward can be detected.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
19
Inclusion Criteria
  1. BMI between 18.5-40 kg/m2
  2. Not pregnant or planning to become pregnant during study participation
  3. Residing in the Roanoke area and/or willing/able to attend sessions at the Fralin Biomedical Research Institute
  4. Able to speak and write in English
  5. Specific to fMRI scan only: BMI between 25-35 kg/m2
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Exclusion Criteria
  1. Current inhaled nicotine use
  2. History of alcohol dependence.
  3. Current or past diagnosis of diabetes or thyroid problems.
  4. Glycated hemoglobin (Hemoglobin A1C) >5.7%
  5. Taking medications known to influence study measures (including antiglycemic agents, thyroid medications, sleep medications)
  6. Active medical or neurologic disorder.
  7. Recent change in body weight (gain or loss of > 5 lbs within the past 3 months)
  8. Current shift work (typical pattern of work/activity overnight)
  9. Previous weight loss surgery
  10. Adherence to a special diet within the past 3 months (e.g., low-carb or ketogenic diet, exclusion of food groups/specific macronutrients, intermittent fasting, etc.)
  11. Allergy to any food or ingredient included in the study diets, meals, or beverages
  12. Currently pregnant or planning to become pregnant during study participation
  13. Claustrophobia
  14. Contraindications for MRI, including pacemaker, aneurysm clips, neurostimulators, cochlear or other implants, metal in eyes, regular work with steel, etc. (Note: This is an fMRI-specific exclusion criterion. Participants may be allowed to participate in all other study sessions and measures that do not involve fMRI.)
  15. Contraindications for bioelectrical impedance analysis, specifically implanted devices
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Study & Design

Study Type
INTERVENTIONAL
Study Design
CROSSOVER
Arm && Interventions
GroupInterventionDescription
Conditioned Stimulus+ (CS+) and High Fat Test Meal FirstHigh-Fat Test Meal Inside a Metabolic ChamberParticipants will undergo exposure sessions with flavored beverage solutions containing sucrose first. They will also undergo the high fat meal test session inside the metabolic chamber first. Then, they will undergo exposure sessions with flavored beverages containing sucralose and the high carbohydrate test meal session.
Conditioned Stimulus+ (CS+) and High Carbohydrate Test Meal FirstHigh-Carbohydrate Test Meal Inside a Metabolic ChamberParticipants will undergo exposure sessions with flavored beverage solutions containing sucrose first. They will also undergo the high carbohydrate meal test session inside the metabolic chamber first. Then, they will undergo exposure sessions with flavored beverages containing sucralose and the high fat test meal session.
Conditioned Stimulus- (CS-) and High Fat Test Meal FirstHigh-Carbohydrate Test Meal Inside a Metabolic ChamberParticipants will undergo exposure sessions with flavored beverage solutions containing sucralose first. They will also undergo the high fat meal test session inside the metabolic chamber first. Then, they will undergo exposure sessions with flavored beverages containing sucrose and the high carbohydrate test meal session.
Conditioned Stimulus- (CS-) and High Carbohydrate Test Meal FirstHigh-Fat Test Meal Inside a Metabolic ChamberParticipants will undergo exposure sessions with flavored beverage solutions containing sucralose first. They will also undergo the high carbohydrate meal test session inside the metabolic chamber first. Then, they will undergo exposure sessions with flavored beverages containing sucrose and the high fat test meal session.
Conditioned Stimulus+ (CS+) and High Carbohydrate Test Meal FirstHigh-Fat Test Meal Inside a Metabolic ChamberParticipants will undergo exposure sessions with flavored beverage solutions containing sucrose first. They will also undergo the high carbohydrate meal test session inside the metabolic chamber first. Then, they will undergo exposure sessions with flavored beverages containing sucralose and the high fat test meal session.
Conditioned Stimulus+ (CS+) and High Fat Test Meal FirstHigh-Carbohydrate Test Meal Inside a Metabolic ChamberParticipants will undergo exposure sessions with flavored beverage solutions containing sucrose first. They will also undergo the high fat meal test session inside the metabolic chamber first. Then, they will undergo exposure sessions with flavored beverages containing sucralose and the high carbohydrate test meal session.
Conditioned Stimulus- (CS-) and High Carbohydrate Test Meal FirstHigh-Carbohydrate Test Meal Inside a Metabolic ChamberParticipants will undergo exposure sessions with flavored beverage solutions containing sucralose first. They will also undergo the high carbohydrate meal test session inside the metabolic chamber first. Then, they will undergo exposure sessions with flavored beverages containing sucrose and the high fat test meal session.
Conditioned Stimulus- (CS-) and High Fat Test Meal FirstHigh-Fat Test Meal Inside a Metabolic ChamberParticipants will undergo exposure sessions with flavored beverage solutions containing sucralose first. They will also undergo the high fat meal test session inside the metabolic chamber first. Then, they will undergo exposure sessions with flavored beverages containing sucrose and the high carbohydrate test meal session.
Primary Outcome Measures
NameTimeMethod
Change in preference- liking15-minute measurement

Subjective ratings of liking of flavors used in the intervention will be assessed at baseline and after the intervention. The generalized Labeled Magnitude Scale will be used. The scale is anchored by descriptors of "Most Disliked Sensation Imaginable" and "Most Liked Sensation Imaginable" at the lower and upper ends, respectively. The score is determined by the place on the scale participants select (range of scale is 0-100). An increase in score from baseline to post-intervention indicates an increase in liking.

Secondary Outcome Measures
NameTimeMethod
Substrate oxidation response to test meals6-hour measurement

Indirect calorimetry in a metabolic chamber will be used to assess substrate oxidation response to high-fat and high-carbohydrate test meals.

Blood glucose response to beverages2-hour measurement

Blood glucose will be assessed at baseline and at set time points for 2 hours after consumption of intervention beverages in one exposure session.

Substrate oxidation in response to beverages1.5-hour measurement

Indirect calorimetry will be used to determine substrate oxidation at baseline (for 30 minutes) and for 1 hour after consumption of intervention beverages in an exposure session.

Blood insulin response to beverages2-hour measurement

Blood insulin will be assessed at baseline and at set time points for 2 hours after consumption of intervention beverages in an exposure session.

Energy expenditure in response to beverages1.5-hour measurement

Indirect calorimetry will be used to determine energy expenditure at baseline (for 30 minutes) and for 1 hour after consumption of intervention beverages in an exposure session.

Blood oxygen level-dependent (BOLD) response to beverages30-minute measurement

In a post-test session, functional magnetic resonance imaging (fMRI) scans will be performed while beverages (without calories) used during the intervention are delivered through a custom manifold fitted to a head coil and connected to a pump system that allows precisely timed and measured delivery of liquids.

Change in preference- wanting5-minute measurement

Forced choice will be used as a measure of wanting in a post-test session. Participants will be provided each of the beverages used during the intervention and asked to choose 1 to take home with them.

Respiratory exchange ratio in response to beverages1.5-hour measurement

Indirect calorimetry will be used to determine respiratory exchange ratio at baseline (for 30 minutes) and for 1 hour after consumption of intervention beverages in an exposure session.

Trial Locations

Locations (1)

Fralin Biomedical Research Institute at Virginia Tech Carilion

🇺🇸

Roanoke, Virginia, United States

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