MedPath

Visceral Adiposity, Vagal Tone and Food Preferences: a Pilot Study

Recruiting
Conditions
Adiposity
Food Preferences
Eating Behavior
Interventions
Other: Visceral adiposity
Registration Number
NCT06175988
Lead Sponsor
Laval University
Brief Summary

Food preferences are defined by a number of measurable parameters, such as per se food choices, sensitivity of taste and olfactory sensory perceptions, hedonic appreciation of foods ("liking") and motivation to consume them ("wanting"). These food preferences are fundamental to the quality of food intake, and are therefore a key factor influencing weight loss or maintenance of a stable weight. Obesity is also associated with reduced sensory sensitivity to taste and smell, as well as disturbances in the responses of the food reward system.

However, the internal, or physiological, mechanisms impacting these food preferences are still poorly understood. To date, several studies seem to point to the role of body composition, in particular visceral adiposity, or adiposity surrounding the digestive organs. Indeed, a high level of visceral adiposity is associated with the onset of numerous cardiometabolic disorders, but also with altered sensory perceptions.

This relationship could be mediated by the vagus nerve, which connects the digestive organs to the brain, enabling the perception of internal signals sent by the body, such as feelings of hunger or satiety. Low vagal activity is associated not only with abdominal obesity, but also with reduced sensory sensitivity to taste and smell, and changes in food choices in favor of energy-dense foods (rich in fats and/or sugars). Electrical stimulation of the vagus nerve is now recognized as a possible treatment for morbid obesity in the USA, but the mechanisms leading to the expected weight loss are still debated. Similarly, an increase in vagal tone has been found in patients who have undergone bariatric surgery for the treatment of severe complicated to morbid obesity, in parallel with sensory disturbances.

The overall aim of this project is to explore and confirm the relationship between visceral adiposity and various food preference parameters, such as olfactory and gustatory perceptions and reward system responses, involving liking and wanting certain foods and associated behaviors. This project also aims to shed light on the possible mediation of the vagus nerve in this relationship.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
70
Inclusion Criteria
  • Have a BMI between 18.5 and 35 kg/m²;
  • French-speaking;
  • Be able to travel to the Research Center of the Institut Universitaire de Cardiologie et Pneumologie de Québec for an investigative visit.
Exclusion Criteria
  • Smokers ;
  • Women who know they are pregnant, breastfeeding or menopausal;
  • Who have been diagnosed with type I or type II diabetes;
  • Having undergone bariatric surgery or obesity medication (GLP1 analogue, naltrexon-bupropion combination, etc.);
  • Presenting an allergy or intolerance to one of the products used in the sensory tests (taste test: sucrose, sodium chloride, citric acid, quinine hydrochloride dihydrate; olfactory test: citrus, lemongrass, cinnamon, mint, peppermint, banana, anise, turpentine, garlic, coffee, apple, clove, pineapple, rose, geranium, eucalyptus, wormwood, fennel, caraway, leather, n-butanol, linalool, pyridine, diethyl phthalate, propylene glycol);
  • Have a history of pathologies which, in the investigator's opinion, could interfere with the study criteria, such as ENT, neurological, upper digestive or cardiac pathologies;
  • Receiving long-term pharmacological treatment, in particular antidepressants, antipsychotics, benzodiazepines, beta-blockers, etc. ;
  • Presenting or having presented in the last 6 months a thymic episode such as depression, bipolar disorder, etc. ;
  • Wearing a cardiostimulator (pacemaker);
  • Minors or adults under guardianship.

Study & Design

Study Type
OBSERVATIONAL
Study Design
Not specified
Arm && Interventions
GroupInterventionDescription
Visceral AdiposityVisceral adiposityNo intervention to be adminstrated. Participants will be considered based on their visceral adiposity (ctageorial and continous). Visceral adiposity index is computed with BMI, waist circumference, triglyceridemia, HDL-cholesterol levels, and biological sex.
Primary Outcome Measures
NameTimeMethod
"Explicit wanting" score for low-fat/savoury foodsBaseline

"Explicit wanting" will be measured using visual analog scales anchored at each end with "not at all" and "extremely" to answer the question "How much would like to eat some of this food now?" while seeing pictures of food items. (/100) The task used is the "Leeds Food Preference Questionnaire".

TDI score, or "Sniffin Sticks" total scoreBaseline

Olfaction score based on odor detection (Threshold), Discrimination, and Identification (/48). The test used is "Sniffin Sticks" (ODOFIN, Burghart Messtechnik GmbH, Holm, Germany).

"Explicit liking" score for high-fat/sweet foodsBaseline

"Explicit liking" will be measured using visual analog scales anchored at each end with "not at all" and "extremely" to answer the question "How pleasant would it be to taste this food now?" while seeing pictures of food items. (/100) The task used is the "Leeds Food Preference Questionnaire".

"Explicit liking" score for low-fat/high-sweet foodsBaseline

"Explicit liking" will be measured using visual analog scales anchored at each end with "not at all" and "extremely" to answer the question "How pleasant would it be to taste this food now?" while seeing pictures of food items. (/100) The task used is the "Leeds Food Preference Questionnaire".

"Explicit liking" score for low-fat/savoury foodsBaseline

"Explicit liking" will be measured using visual analog scales anchored at each end with "not at all" and "extremely" to answer the question "How pleasant would it be to taste this food now?" while seeing pictures of food items. (/100) The task used is the "Leeds Food Preference Questionnaire".

"Explicit liking" score for high-fat/savoury foodsBaseline

"Explicit liking" will be measured using visual analog scales anchored at each end with "not at all" and "extremely" to answer the question "How pleasant would it be to taste this food now?" while seeing pictures of food items. (/100) The task used is the "Leeds Food Preference Questionnaire".

"Explicit wanting" score for low-fat/sweet foodsBaseline

"Explicit wanting" will be measured using visual analog scales anchored at each end with "not at all" and "extremely" to answer the question "How much would like to eat some of this food now?" while seeing pictures of food items. (/100) The task used is the "Leeds Food Preference Questionnaire".

"Implicit wanting" score for high-fat/savoury foodsBaseline

"Implicit wanting" will be calculated using a forced-choice task. It involves the presentation of successive pairs of food pictures, each pair being the object of a spontaneous preferential choice by the volunteer. A score is calculated from the frequency of choice and non-choice of said category and the reaction time of the participants. This score ranges from -100 to 100 and is interpreted in relation to the scores for the other food categories assessed in the task. A positive score indicates that the food category under consideration was chosen more often and more quickly than the others. A negative score indicates the opposite. The task used is the "Leeds Food Preference Questionnaire".

"Taste Strips" total scoreBaseline

Taste identification score for sweet, salty, bitter, and sour (/16). The test used is "Taste Strips" (ODOFIN, Burghart Messtechnik GmbH, Holm, Germany).

"Explicit wanting" score for high-fat/sweet foodsBaseline

"Explicit wanting" will be measured using visual analog scales anchored at each end with "not at all" and "extremely" to answer the question "How much would like to eat some of this food now?" while seeing pictures of food items. (/100) The task used is the "Leeds Food Preference Questionnaire".

"Explicit wanting" score for high-fat/savoury foodsBaseline

"Explicit wanting" will be measured using visual analog scales anchored at each end with "not at all" and "extremely" to answer the question "How much would like to eat some of this food now?" while seeing pictures of food items. (/100) The task used is the "Leeds Food Preference Questionnaire".

"Implicit wanting" score for high-fat/sweet foodsBaseline

"Implicit wanting" will be calculated using a forced-choice task. It involves the presentation of successive pairs of food pictures, each pair being the object of a spontaneous preferential choice by the volunteer. A score is calculated from the frequency of choice and non-choice of said category and the reaction time of the participants. This score ranges from -100 to 100 and is interpreted in relation to the scores for the other food categories assessed in the task. A positive score indicates that the food category under consideration was chosen more often and more quickly than the others. A negative score indicates the opposite. The task used is the "Leeds Food Preference Questionnaire".

"Implicit wanting" score for low-fat/sweet foodsBaseline

"Implicit wanting" will be calculated using a forced-choice task. It involves the presentation of successive pairs of food pictures, each pair being the object of a spontaneous preferential choice by the volunteer. A score is calculated from the frequency of choice and non-choice of said category and the reaction time of the participants. This score ranges from -100 to 100 and is interpreted in relation to the scores for the other food categories assessed in the task. A positive score indicates that the food category under consideration was chosen more often and more quickly than the others. A negative score indicates the opposite. The task used is the "Leeds Food Preference Questionnaire".

"Implicit wanting" score for low-fat/savoury foodsBaseline

"Implicit wanting" will be calculated using a forced-choice task. It involves the presentation of successive pairs of food pictures, each pair being the object of a spontaneous preferential choice by the volunteer. A score is calculated from the frequency of choice and non-choice of said category and the reaction time of the participants. This score ranges from -100 to 100 and is interpreted in relation to the scores for the other food categories assessed in the task. A positive score indicates that the food category under consideration was chosen more often and more quickly than the others. A negative score indicates the opposite. The task used is the "Leeds Food Preference Questionnaire".

Secondary Outcome Measures
NameTimeMethod
Fasting InsulinemiaBaseline

Fasting blood sample. (pmol/L)

Standard deviation of the N-N interval (SDNN)Baseline

Parameter of the heart rate variability, indirect indicator of the vagal tone (ms). Standard deviation of NN intervals. Measured using a 48 hours Holter monitor.

Satiety volume as a percentage of total volume (Water Load Task)Baseline

Indicator of gastric interoceptive capacities obtained during the "Water Load Task".

CCK fasting blood levelsBaseline

Fasting blood sample. (mmol/L)

Root mean square of successive N-N interval difference (RMSSD)Baseline

Parameter of the heart rate variability, indirect indicator of the vagal tone (ms). Root mean square of successive R-R interval differences. Measured using a 48 hours Holter monitor.

High Frequency (HF)Baseline

Parameter of the heart rate variability, indirect indicator of the vagal tone (ms²). Power spectral density of high frequencies. Measured using a 48 hours Holter monitor.

LPS fasting blood levelsBaseline

Associated with adipose tissue dysfunction. Fasting blood sample. (mmol/L)

IL-6 fasting blood levelsBaseline

Associated with adipose tissue dysfunction. Fasting blood sample. (mmol/L)

Sweet Perceived IntensityBaseline

Measured during the "Taste Strips" using "9 Likert scales" ranging from "no taste" to "intense" will be used. A score ranging from 1 to 9 will be calculated.

Bitter Perceived IntensityBaseline

Measured during the "Taste Strips" using "9 Likert scales" ranging from "no taste" to "intense" will be used. A score ranging from 1 to 9 will be calculated.

Sour Perceived IntensityBaseline

Measured during the "Taste Strips" using "9 Likert scales" ranging from "no taste" to "intense" will be used. A score ranging from 1 to 9 will be calculated.

Sweet Perceived AppreciationBaseline

Measured during the "Taste Strips" using "9 Likert scales" ranging from "extremely unpleasant" to "extremely pleasant" will be used. A score ranging from 1 to 9 will be calculated.

Salty Perceived AppreciationBaseline

Measured during the "Taste Strips" using "9 Likert scales" ranging from "extremely unpleasant" to "extremely pleasant" will be used. A score ranging from 1 to 9 will be calculated.

Sour Perceived AppreciationBaseline

Measured during the "Taste Strips" using "9 Likert scales" ranging from "extremely unpleasant" to "extremely pleasant" will be used. A score ranging from 1 to 9 will be calculated.

Odors Perceived AppreciationBaseline

Measured during the "Sniffin Sticks" (identification test) using "9 Likert scales" ranging from "extremely unpleasant" to "extremely pleasant" will be used. A score ranging from 1 to 9 will be calculated.

Food Craving Trait Questionnaire (FCQ T) scoreBaseline

Evaluates severity of cravings using a validated questionnaire. Minimum : 39; Maximum : 234; Higher scores mean a worse outcome.

PYY fasting blood levelsBaseline

Fasting blood sample. (mmol/L)

Fasting GlycemiaBaseline

Fasting blood sample. (mmol/L)

LF/HF ratioBaseline

Parameter of the heart rate variability, indirect indicator of the vagal tone (a.u.). Measured using a 48 hours Holter monitor.

Odors Perceived IntensityBaseline

Measured during the "Sniffin Sticks" (identification test) using "9 Likert scales" ranging from "no odor" to "intense" will be used. A score ranging from 1 to 9 will be calculated.

Eating Disorder Examination Questionnaire (EDE-Q) scoreBaseline

Evaluates presence of eating disorders using a validated questionnaire. The measure provides four attitudinal subscale scores: Restraint (5 items), Eating Concern (5 items), Shape Concern (8 items), and Weight Concern (5 items). An overall Global score is the mean of the four subscale scores. Responses are on a 7-point ordinal response; minimum score : 0, maximun score: 6; higher scores mean a worse outcome.

Food Craving State Questionnaire (FCQ S) scoreBaseline

Evaluates severity of cravings using a validated questionnaire. Minimum : 15; Maximum : 75; Higher scores mean a worse outcome.

Body Awareness Questionnaire (BAQ) scoreBaseline

Evaluates attention to intern signals (interoception) using a validated questionnaire. Minimum score: 18; Maximun score: 126; Higher scores mean a better outcome.

GLP-1 fasting blood levelsBaseline

Fasting blood sample. (mmol/L)

Glicentine fasting blood levelsBaseline

Fasting blood sample. (mmol/L)

pNN50Baseline

Parameter of the heart rate variability, indirect indicator of the vagal tone (%). Percentage of successive R-R intervals that differ by more than 50 ms. Measured using a 48 hours Holter monitor.

Low Frequency (LF)Baseline

Parameter of the heart rate variability, indirect indicator of the vagal tone (ms²). Power spectral density of low frequencies. Measured using a 48 hours Holter monitor.

Salty Perceived IntensityBaseline

Measured during the "Taste Strips" using "9 Likert scales" ranging from "no taste" to "intense" will be used. A score ranging from 1 to 9 will be calculated.

Bitter Perceived AppreciationBaseline

Measured during the "Taste Strips" using "9 Likert scales" ranging from "extremely unpleasant" to "extremely pleasant" will be used. A score ranging from 1 to 9 will be calculated.

Beck Depression Inventory II (BDI-II) scoreBaseline

Evaluates severity of depressive symptoms using a validated questionnaire. Minimum score : 0; Maximun score : 63; Higher scores mean a worse outcome.

State-Trait Anxiety Inventory (STAI) scoreBaseline

Evaluates severity of anxiety symptoms using a validated questionnaire. The questionnaire includes two scales (20 items) consisting of a total of 40 questions. For each scale the minimum score is 0 and the maximun score is 80. Higher scores mean a worse outcome.

Oxytomodulin fasting blood levelsBaseline

Fasting blood sample. (mmol/L)

Appetite scoresBaseline

Calculated on the basis of a rating from 0 to 10 for each of the following parameters: sensation of hunger, desire to eat, satiation and prospective consumption. These ratings will be estimated using 100 mm-long visual analog scales annotated with "not at all" and "extremely", on the left and right of the scale respectively, to answer the following questions: "At the moment, how hungry are you?", "At the moment, how hungry are you?", "At the moment, how hungry are you?" and "At the moment, how hungry do you think you are?".

Before each tests on the exploration day (taste, olfaction, LFPQ, Water Load Task, questionnaires)

Trial Locations

Locations (1)

IUCPQ

🇨🇦

Québec, Quebec, Canada

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