Mechanisms Underlying Individual Variations of Taste and Smell in Obesity

Launched by NATIONAL INSTITUTE ON ALCOHOL ABUSE AND ALCOHOLISM (NIAAA) · Jan 19, 2021

Keywords

ClinConnect Summary

This clinical trial is studying how our senses of taste and smell influence eating habits and may contribute to obesity. Researchers want to understand why some people with obesity experience different tastes and smells compared to those without obesity. By exploring these differences, they hope to learn more about how our senses can affect food choices and overall health.

To participate, you need to be an adult aged 18 to 65, and you should either have a body mass index (BMI) in the obesity range or be a healthy weight. The study involves two visits where you will answer questions about your eating habits, undergo tests for your sense of taste and smell, and provide samples like blood and urine for testing. You will also have your weight and body measurements taken. Participants will get a meal to eat during the study, and you’ll track your daily activities and sleep. This trial is currently recruiting, so if you’re interested and meet the criteria, you could contribute to important research on obesity and our senses.

Gender

ALL

Eligibility criteria

• * 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
• • 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
• EXCLUSION CRITERIA:
• An individual who meets any of the following criteria will be excluded from participation in this study:
• • Because type-2 diabetic subjects have blunted taste responses, subjects with diagnosis of type II diabetes will be excluded.
• • Hypoglycemic drug intake.
• • Weight change of more than 15 pounds in the 6 months prior to screening
• • Positive pregnancy test, currently pregnant or breastfeeding.
• • 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.
• • 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.
• • Use of tobacco products or illicit drugs (as determined by urine drug screen and/or history/physical exam) in the last 30 days.
• • 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.
• • 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 \[National Heart, Lung and Blood Institute (NHLBI) definition (Anemia - Iron-Deficiency Anemia, Diagnosis NHLBI, NIH)\].
• • Bariatric surgery within the last 12 months of screening.
• • 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).
• • Altered cranial nerves identified by neurological evaluation during physical exam (screening visit).
• • Currently experiencing temporary change/loss of taste and/or smell.
• • Persistent loss of taste and/or smell due to COVID-19 or other reasons.
• • 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.