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The Chocolate Study 2.0

Assessment of Dopaminergic Neurotransmission in Response to Tasting Chocolate (The Chocolate Study 2.0)

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04037020
Enrollment
20
Registered
2019-07-30
Start date
2019-07-25
Completion date
2019-09-05
Last updated
2025-04-11

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Normal Weight

Brief summary

The purpose of this study is to test how the brain responds when enjoyable foods such as chocolate are consumed. The investigators know that eating certain types of foods can make an individual want to keep eating even when he or she is full. The chemical in the brain that causes this is called dopamine. The investigators can measure this response by looking at changes to how an individual's eye responds to light.

Detailed description

The overall objective of this study is to determine dopamine (DA) neuromodulation (changes in b-wave amplitude as measured by electroretinography (ERG)) in response to consuming a highly reinforcing food (chocolate). The investigators hypothesize that orosensory stimulation with chocolates with increasing sugar content will increase the beta wave (b-wave) amplitude and the increase in the b-wave amplitude will correlate with score changes on the Psychophysical Effects Questionnaire (PEQ). This will be accomplished by testing different chocolates (extreme dark (90% cocoa), dark (70% cocoa), milk (38% cocoa), and white (0% cocoa)) on different days using 1.0 cd∙s/m2 flash luminance energy.

Interventions

Participants will be asked to taste commercially available chocolate varying in sugar, fat and percent cocoa (extreme dark (90%), dark (70%), milk (38%), and white (0%)).

Sponsors

USDA Grand Forks Human Nutrition Research Center
Lead SponsorFED

Study design

Observational model
COHORT
Time perspective
OTHER

Eligibility

Sex/Gender
ALL
Age
18 Years to 30 Years
Healthy volunteers
Yes

Inclusion criteria

* BMI 20-24.9 kg/m2 * ability to understand and sign the consent form * availability of transportation (i.e., participants must be able to provide their own transportation to the Grand Forks Human Nutrition Research Center) * be free of any major illness/disease

Exclusion criteria

* food allergies * participation in a weight loss diet/exercise program * pregnancy * lactation * metabolic illness/disease (diabetes, renal failure, thyroid illness, hypertension) * eye illness/disease (narrow angle glaucoma, macular degeneration, retinal detachment, cataracts) * psychiatric, neurological or eating disorders (schizophrenia, depression, Parkinson's Disease, Huntington's Disease, cerebral palsy, stroke, epilepsy, anorexia nervosa or bulimia nervosa) * taking any type of prescription medication with the exception of oral contraceptives and antihyperlipidemia agents

Design outcomes

Primary

MeasureTime frameDescription
Retinal dopamine response to oral stimuli30 minutesElectroretinograph b-wave amplitude will increase in response to increases in the amount of sugar in the chocolate.

Secondary

MeasureTime frameDescription
Correlation between b-wave amplitude and PEQ scores30 minutesThe change in b-wave amplitude will positively correlate to Psychophysical Effects Questionnaire (PEQ) score changes.
Correlation between b-wave amplitude and habitual dietary intake30 minutesA preference for dark chocolate and/or a greater habitual fat intake will positively correlate with the retinal dopamine-mediated response to the dark chocolates (90% and 70% cocoa) and a preference for milk chocolate and/or a greater habitual added sugar will positively correlate with the retinal dopamine-mediated response to the milk and white chocolates. Higher amounts of artificial sweetener intake will will positively correlate with the retinal dopamine-mediated response to the milk and white chocolates. Greater habitual chocolate intake will positively correlate to changes in b-wave amplitude.

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026