Appetite, Eating Behavior, Obesity, Olfaction, Overweight, Taste Perception
Conditions
Keywords
GLP-1 receptor agonists, taste, smell, olfaction, food preferences, food craving, appetite, Food cue responsivity, Salivary response
Brief summary
The goal of this study is to explore whether of GLP-1 receptor agonist use is associated with differences in taste, smell, food preferences, appetite, food cravings, and responses to food cues in adults. The study includes adults who are not currently taking a GLP-1 receptor agonist but may be eligible to use one, and adults who are already taking a GLP-1 receptor agonist as part of their regular medical care for approximately 1 month or approximately 6 months. The main questions it aims to answer are: Are taste and smell function different among adults who are not taking a GLP-1 receptor agonist and adults who have been taking one for different lengths of time? Are food preferences, appetite, food cravings, food reward, attention to food cues, and salivary responses to food cues different among these groups? Researchers will compare adults not currently taking a GLP-1 receptor agonist with adults taking a GLP-1 receptor agonist for approximately 1 month or approximately 6 months. The research team will not prescribe, assign, or provide GLP-1 receptor agonist medications. People in the study will attend two in-person study visits, complete taste and smell tests, complete food preference and computer-based tasks, and provide saliva samples during a food cue task. Questionnaires about appetite, cravings, food cues, and eating behavior will be completed at home over approximately 2 weeks.
Detailed description
This cross-sectional study examines associations between GLP-1 receptor agonist use, chemosensory function, and ingestive behavior in adults. People enrolled in the study are classified into groups based on GLP-1 receptor agonist use status and duration of use: adults who are not currently taking a GLP-1 receptor agonist but may be eligible to use one, adults taking a GLP-1 receptor agonist for approximately 1 month, and adults taking a GLP-1 receptor agonist for approximately 6 months. GLP-1 receptor agonist use is not assigned by the research team. People who are taking these medications are using them as part of their regular medical care. The study team does not prescribe, administer, or change GLP-1 receptor agonist treatment. Study procedures include assessments of taste and smell function, food preferences, food reward, appetite, food cravings, food cue responsivity, attentional responses to food cues, and salivary responses to a food cue. Outcomes will be compared across groups to explore whether GLP-1 receptor agonist use and duration of use are associated with differences in chemosensory function and ingestive behavior.
Interventions
None listed
Sponsors
Purdue University
Study design
Observational model
COHORT
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
18 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
* Ages 18 to 65 years. * Any sex or gender. * Body Mass Index (BMI) \>30 kg/m². * Stable medication use, excluding weight management medications other than GLP-1 receptor agonist use as part of regular medical care. * Eligible to take GLP-1 receptor agonists but not yet started treatment, or currently taking GLP-1 receptor agonists for weight management for approximately 1 month (±0.5 months) or approximately 6 months (±0.5 months). * No known sensitivity or allergy to study solutions or foods, including sweet solutions, salty solutions, sour solutions, bitter solutions, fatty stimuli, common food flavors used in testing, milk, and fruit-flavored beverages.
Exclusion criteria
* Younger than 18 years or older than 65 years. * Previous bariatric surgery or planned bariatric surgery within the next year. * Sensitivity or allergy to study foods, taste solutions, odor stimuli, or food-related test materials.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Taste Detection Thresholds | During study participation, up to 2 weeks | Taste detection thresholds will be assessed for sweet, salty, sour, and bitter stimuli (sucrose, sodium chloride, citric acid, and urea, respectively) using a two-alternative forced-choice staircase procedure, in which participants identify which of two samples contains the taste stimulus. Separate outcomes will be reported for each taste quality: sweet, salty, sour, and bitter. For each taste quality, the threshold will be calculated as the geometric mean concentration at which the stimulus is reliably detected and will be reported in mmol/L. Lower threshold values indicate greater taste sensitivity. |
| Suprathreshold Taste Intensity | During study participation, up to 2 weeks | Suprathreshold taste intensity will be assessed for sweet, salty, sour, and bitter stimuli (sucrose, sodium chloride, citric acid, and urea, respectively) using the general Labeled Magnitude Scale. Separate outcomes will be reported for each taste quality and stimulus concentration. For each taste quality, participants will rate the perceived intensity of suprathreshold stimulus concentrations. The scale ranges from 0 to 100, with 0 anchored by "no sensation" and 100 anchored by "strongest imaginable sensation of any kind." Higher scores indicate greater perceived taste intensity. |
| Taste Hedonics | During study participation, up to 2 weeks | Taste hedonics will be assessed using a food modification task in which participants create preferred concentrations for sweet, salty, sour, bitter, and fatty stimuli. Separate outcomes will be reported for each stimulus type: sweet, salty, sour, bitter, and fatty. For each stimulus type, the outcome will be the preferred concentration selected by the participant. Higher values indicate preference for a higher concentration of that stimulus and do not necessarily indicate a better or worse outcome. |
| Fat Taste Intensity Rating | During study participation, up to 2 weeks | Fat taste perception will be assessed using edible strips containing different concentrations of linoleic acid. Participants will rate the perceived intensity of each strip using the general Labeled Magnitude Scale. Separate outcomes will be reported for each linoleic acid concentration. The scale ranges from 0 to 100, with 0 anchored by "no sensation" and 100 anchored by "strongest imaginable sensation of any kind." Higher scores indicate greater perceived fat taste intensity. |
| ArOMa-T Olfactory Test Performance | During study participation, up to 2 weeks | Olfactory function will be assessed using the ArOMa-T test. Participants will smell odor stimuli and provide computer-based responses to questions assessing olfactory performance. The outcome will be the ArOMa-T test score, with higher scores indicating better olfactory performance. |
| SCENTinel Olfactory Test Performance | During study participation, up to 2 weeks | Olfactory function will be assessed using the SCENTinel test. Participants will smell odor stimuli and provide computer-based responses to questions assessing odor detection, odor identification, odor intensity, and odor pleasantness. Separate outcomes will be reported for each SCENTinel component. Higher scores indicate better odor detection or identification performance, greater perceived odor intensity, or greater perceived odor pleasantness, depending on the component assessed. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Food Preferences | During study participation, up to 2 weeks | Food preferences will be assessed using the Leeds Food Preference Questionnaire. Participants will view food images and rate how much they like and want to eat each food item. Ratings will be used to assess explicit liking and wanting for foods. |
| Attentional Bias to Food Cues | During study participation, up to 2 weeks | Attentional bias to food cues will be assessed using a Food Stroop Task. Participants will view food-related and non-food words and respond to the color of each word while ignoring the meaning of the word. Response patterns will be used to assess attentional bias toward food-related cues. |
| Questionnaire-Based Measures of Food Cravings, Food Cue Responsivity, Food Noise, and Eating Behavior | During study participation, up to 2 weeks | Questionnaire-based measures will be used to assess food cravings, food cue responsivity, food-related intrusive thoughts, perceived food reward, and eating behavior. Participants will complete the Food Cue Responsivity Scale, the Modified Trait and State Food Cravings Questionnaires, the Power of Food Scale, the Food Noise Questionnaire, and the Reasons Individuals Stop Eating Questionnaire. These questionnaires will assess sensitivity to food-related cues, typical and momentary food cravings, food-related intrusive thoughts, perceived responsiveness to the food environment, and reasons for stopping eating, including motivations and physical cues related to meal termination and satisfaction. |
| Dietary Intake | During study participation, up to 2 weeks | Dietary intake will be assessed using ASA24, the Automated Self-Administered 24-Hour Dietary Assessment Tool. Participants will complete three 24-hour dietary recalls on different days, including two weekdays and one weekend day, to report foods and beverages consumed over the previous 24 hours. |
| Cephalic-Phase Salivary Response | During study participation, up to 2 weeks | Cephalic-phase salivary response will be assessed by measuring saliva production at baseline and during exposure to a food cue. Saliva will be collected during a baseline period and again while participants simulate eating a food item by focusing on its smell, taste, and texture. Saliva will be collected in graduated tubes and weighed to quantify salivary output. Change in salivation from baseline to food cue exposure will be compared across groups. |
Countries
United States
Contacts
PRINCIPAL_INVESTIGATORRichard D Mattes, PhD, RD, MPH
Purdue University
Outcome results
None listed