NCT06053294 · Virginia Polytechnic Institute and State University
Neural and Metabolic Factors in Carbohydrate Reward
(CARB)
What this study is about
Dietary factors contributed to nearly 50% of all cardiometabolic deaths in the US in 2012, making it one of the leading causes of preventable death in the US, second only to tobacco use.
View original scientific description
Dietary factors contributed to nearly 50% of all cardiometabolic deaths in the US in 2012, making it one of the leading causes of preventable death in the US, second only to tobacco use. Human diets and food choices can't help but be influenced by the ubiquitous availability of processed foods of high-energy density and low nutrient content, consumption of which can lead to obesity, type II diabetes, heart disease, and other types of metabolic dysfunction. Surprisingly, food reinforcement does not rely on perceived energy density. Rather food reinforcement is associated with actual energy density and therefore, on an implicit knowledge of caloric content. That implicit knowledge must have a neural signature and a mechanism by which the gut communicates nutritive value to the brain. There is evidence, at least for fat and carbohydrates, that these pathways are separable, but terminate in a common neural structure, the dorsal striatum or caudate. This could be one mechanism by which modern processed foods high in both fat and carbohydrate are so sought after and readily consumed, In fact, when experimentally tested, fat and carbohydrate combinations were more reinforcing calorie for calorie than fat or carbohydrates alone and the level of reinforcement correlated with activity in reward- related brain areas. Beyond simple reinforcing value, it is known from the literature on drugs of abuse that the faster a drug is arrives at the brain, the higher it's abuse potential, however, little is known about how the kinetics of nutrient excursion influence food preference, choice, and brain activity. This project aims to test this specifically for carbohydrate reward.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- BMI between 18.5-30 kg/m2
- Not pregnant or planning to become pregnant during study participation
- Residing in the Roanoke area and/or willing/able to attend sessions at the Fralin Biomedical Research Institute
- Able to speak and write in English
Exclusion criteria
- Current inhaled nicotine use
- History of alcohol dependence.
- Current or past diagnosis of diabetes or thyroid problems.
- Taking medications known to influence study measures (including antiglycemic agents, thyroid medications, sleep medications)
- Active medical or neurologic disorder.
- Current shift work (typical pattern of work/activity overnight)
- Previous weight loss surgery
- 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.)
- Allergy to any food or ingredient included in the study diets, meals, or beverages
- Currently pregnant or planning to become pregnant during study participation
- Claustrophobia
- Contraindications for MRI, including pacemaker, aneurysm clips, neurostimulators, cochlear or other implants, metal in eyes, regular work with steel, etc.
Where
- Roanoke, Virginia
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Jul 2, 2026 · Source of record for eligibility and locations