The Role of the Endocannabinoid System in Sweet Taste Intensity and Liking

Study Overview
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Brief Summary
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The endocannabinoid (eCB) system, a neurochemical signalling system consisting of CB-receptors and their endogenous ligands, has been found to be involved in food intake of sweet and palatable foods. Activation of the eCB system increases food intake and vice versa. The mechanism behind this effect is still unknown and the current study aims at clarifying why sweet food intake increases. It is hypothesized that sweet taste intensity increases and that sweet taste is experienced as more pleasant.

Official Title
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The Role of the Endocannabinoid System in Sweet Taste Intensity and Liking

Conditions
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Sensory Science

Intervention / Treatment
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* Drug: tetrahydrocannabinol
* Drug: cannabidiol
* Drug: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: BMI: 18.5 - 25 kg/m2 Incidental cannabis use for at least one year, at least four times per year, but less than once a week. Dutch-speaking Willing to comply with the study procedures Having given written informed consent Exclusion Criteria: Not meeting the inclusion criteria Restraint eating (men: score > 2.90) Lack of appetite Having difficulties with swallowing/eating Usage of an energy restricted diet during the last two months Weight loss or weight gain of 5kg or more during the last two months Stomach or bowel disease Diabetes, thyroid disease, other endocrine disorders Use of daily medication except paracetamol Having taste or smell disorders (self-report) Being allergic/intolerant for products under study Previously experienced an adverse reaction to cannabinoids (e.g. anxiety, paranoia, nausea) Having (had) a schizophrenia or other psychotic illness Having a family history of schizophrenia or other psychotic illness Working at the Division of Human Nutrition (WUR) Current participation in other research from the Division of Human Nutrition (WUR)

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 35 Years

Sexes Eligible for Study
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Male

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
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: T-C-P<br>Order of administrations: tetrahydrocannabinol - cannabidiol - placebo | Drug: tetrahydrocannabinol<br> <br> * Other names: THC;Drug: cannabidiol<br> <br> * Other names: CBD;Drug: Placebo<br> <br> |
| Experimental: T-P-C<br>Order of administrations: tetrahydrocannabinol - placebo - cannabidiol | Drug: tetrahydrocannabinol<br> <br> * Other names: THC;Drug: cannabidiol<br> <br> * Other names: CBD;Drug: Placebo<br> <br> |
| Experimental: C - T - P<br>Order of administrations: cannabidiol - tetrahydrocannabinol - placebo | Drug: tetrahydrocannabinol<br> <br> * Other names: THC;Drug: cannabidiol<br> <br> * Other names: CBD;Drug: Placebo<br> <br> |
| Experimental: C - P - T<br>Order of administrations: cannabidiol - placebo - tetrahydrocannabinol | Drug: tetrahydrocannabinol<br> <br> * Other names: THC;Drug: cannabidiol<br> <br> * Other names: CBD;Drug: Placebo<br> <br> |
| Experimental: P - T - C<br>Order of administrations: placebo - tetrahydrocannabinol - cannabidiol | Drug: tetrahydrocannabinol<br> <br> * Other names: THC;Drug: cannabidiol<br> <br> * Other names: CBD;Drug: Placebo<br> <br> |
| Experimental: P - C - T<br>Order of administrations: placebo - cannabidiol - tetrahydrocannabinol | Drug: tetrahydrocannabinol<br> <br> * Other names: THC;Drug: cannabidiol<br> <br> * Other names: CBD;Drug: Placebo<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Relation between sweet taste intensity and liking | The main study parameter is the relation between sucrose intensity scaling (psychophysics) and liking (psychohedonics) of drinks with the different sucrose concentrations. These scores will be assessed after six participants and at end of the study. | 15 minutes after intervention | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Ranking order of pleasantness of different drinks with different levels of sucrose. | Ranking order will be assessed after 6 participants and at end of the study | 25 minutes after intervention | 
| Preferences for different kinds of foods | Preference for foods high in one of three macronutrients (carbohydrate, protein, fat) or low in energy | 45 minutes after intervention (15 minutes after top-up dose) | 
| Ad libitum intake | Ad libitum intake of a chocolate-based drink | 35 minutes after intervention (5 minutes after top-up dose) | 
| Change of plasma levels of (endo-)cannabinoids and satiety hormones |  | One hour after intervention | 
| Polymorphisms | The genetic determination of the enzymes responsible for the metabolism of THC and CBD. | At test session, i.e., 2 weeks before first intervention |