NCT04714892Recruiting
Mechanisms Underlying Individual Variations of Taste and Smell in Obesity
Source: ClinicalTrials.gov · Last updated 13 Oct 2026
Brief summary (registry, in English)
Background: Changes to the sense of taste or smell can change eating behavior. This may contribute to obesity. Researchers want to see how taste and smell perceptions that affect food choices may differ between people with obesity and without obesity. Objective: To understand the role that senses of taste and smell play in food intake. Eligibility: Adults ages 18-65 with obesity and without obesity Design: Participants will be screened with a medical history and physical exam. They will have a neurological and sensory exam. They will give blood and urine samples. They will be checked for previous SARS-CoV-2 infection. They will complete questionnaires about their eating habits, alcohol use, and smoking history. Participants will have 2 study visits. Participants will give stool, urine, blood, hair, nasal, and saliva samples. These samples will be used for gene testing. Participants will have their weight, height, and hip and waist circumference measured. They will have an imaging scan that measures body composition. Participants will complete questionnaires about their health, eating habits, and food preferences. Participants will have taste tests and smell tests. They will have sensory tests to assess their response to stimuli. Participants will have a dietary assessment. They will complete a food diary and a diet history questionnaire. Participants will get a meal to eat. Data will be collected about their experience. Participants will complete a sleep diary and wear a watch to measure their activity....
- Status (registry)
- Recruiting
- Study type
- Observational
- Enrollment
- 350 (estimated)
- First submitted
- 16 Jan 2021
- Start date
- 11 May 2022
- Primary completion date
- 30 Dec 2026
- Lead sponsor
- National Institute on Alcohol Abuse and Alcoholism (NIAAA)
- Diseases
- Obesity
- NCT number
- NCT04714892
What you commit to
- Study type: Observational
- Planned participants: 350
- From 11 May 2022 to the primary completion date, 30 Dec 2026
- 1 site in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Hypoglycemic drug intake.
- Weight change of more than 15 pounds in the 6 months prior to screening
- Currently using any of the following medications: steroidal or nonsteroidal antiinflammatory medications, medications known to inhibit taste response (GLP1 agonists), antiepileptic or antidepressant agents, glucocorticoids, or antibiotics.
- Received a diagnosis by a medical professional of morbid obesity, liver or renal disease.
- Use of tobacco products or illicit drugs (as determined by urine drug screen and/or history/physical exam) in the last 30 days.
- Bariatric surgery within the last 12 months of screening.
Other illness
- Because type-2 diabetic subjects have blunted taste responses, subjects with diagnosis of type II diabetes will be excluded.
- Currently have an uncontrolled medical disorder (i.e., gastrointestinal, endocrine, cardiac, psychiatric).
- Any self-reported history of chronic rhinitis, eating disorder (including binge eating), chronic upper respiratory infection, chronic allergic rhinitis, or nasal polyps in the last 6 months of screening, or current daily use of nasal sprays.
- History of cancer (e.g., head and neck cancer) and/or history of cancer treatment (e.g., radiotherapy to the head and neck area or chemotherapy).
- Persistent loss of taste and/or smell due to COVID-19 or other reasons.
Lab values
- Abnormal complete blood count (CBC): White Blood Cell Count \< 4 or \> 10 K/uL, Red Blood Cell Count \< 4 or \> 7 M/uL, Hemoglobin \< 12 g/dL for females or \< 13 g/dL for males or any clinical signs/symptoms that indicate iron deficiency anemia per clinician's judgment at screening \[National Heart, Lung and Blood Institute (NHLBI) definition (Anemia - Iron-Deficiency Anemia, Diagnosis; NHLBI, NIH)\].
Other
- An individual who meets any of the following criteria will be excluded from participation in this study:
- Positive pregnancy test, currently pregnant or breastfeeding.
- Individuals with current heavy drinking. Women who drink 4 drinks or more in one occasion and 7 drinks in a week. Men who drink 5 drinks or more in one occasion and more than 14 drinks a week.
- Altered cranial nerves identified by neurological evaluation during physical exam (screening visit).
- Currently experiencing temporary change/loss of taste and/or smell.
- Unable to read and understand English. Since all self-report measures are in English only, participants need to be able to read and understand the English language.
- NIAAA employees/staff or subordinates/relatives/co-workers of NIAAA employees/staff or study investigators.
Criteria the registry did not label
- INCLUSION CRITERIA:
- In order to be eligible to participate in this study, an individual must meet all of the following criteria:
- Males and females between 18 to 65 years of age. Due to documented knowledge that taste and smell changes with age, we will limit the cohort within this age range.
- BMI between 18.5 and 29.9 kg/m\^2 for healthy controls or between 30 and 39.9 kg/m\^2 for obese subjects at screening
- Fasted plasma glucose levels between 68-126 mg/dl or per Clinical Center ranges, and hemoglobin A1C\<6.5%
- Able to provide his/her own consent
- Able to understand the protocol, as shown by scoring a 6 out of 6 on a consent quiz
Age in the registry: 18 years to 65 years · Sex: All · Accepts healthy volunteers
Sites (1)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| National Institutes of Health Clinical Center Coordinator of this site? Confirm its status | Bethesda | United States | Recruiting |
This page is information, not medical advice. Discuss any trial with your doctor.