NCT05677321 · National Institute on Alcohol Abuse and Alcoholism (NIAAA)
Individual Variations of Taste and Smell Perception in Alcohol Use Disorder (AUD)
What this study is about
Background: Alcohol use disorder (AUD) is the most common substance use disorder in the world. Long-term AUD can affect a person s sense of taste and smell. This natural history study will compare alcohol drinking behaviors and measures of taste and smell in people with and without AUD. Objective: To understand how alcohol use changes the senses of taste and smell.
View original scientific description
Background: Alcohol use disorder (AUD) is the most common substance use disorder in the world. Long-term AUD can affect a person s sense of taste and smell. This natural history study will compare alcohol drinking behaviors and measures of taste and smell in people with and without AUD. Objective: To understand how alcohol use changes the senses of taste and smell. Eligibility: People aged 18 to 65 years with or without AUD. Design: Participants will be screened. They will have several tests to assess their smell and taste functions. They will answer questions about their eating, alcohol use, and smoking or vaping habits. Participants will have 2 study visits. They will give samples of blood, nasal mucous, saliva, stool, and urine. Their bodies will be measured. They will undergo a type of scan that uses X-rays to measure their body composition. They will complete taste measurements. They will taste liquids by swishing them in their mouth, without swallowing. Then, they will be asked what they can detect and which flavors they preferred. They will also complete smell measurements. They will be asked if they can identify strong odors on a metal wand. They will be asked to rate the intensity and pleasantness of odors. Their brain activity in the frontal regions will be measured while they smell various odors. For this, we will use a brain imaging tool called functional near infrared spectroscopy. They will have sensory testing. Sensations such as pressure, pinpricks, heat, or vibrations will be applied to their skin. Then, they will be asked what they felt. They will keep diaries. They will write down what they eat (for 3 days), the alcohol they drink (3 days), and how much they sleep (14 days). They will wear a wristwatch-like device that records their activity for 14 days.
Primary outcome measures
Taste and smell measures, alcohol drinking behavior
Time frame: At enrollment
Compare individuals with AUD to those without AUD in measures of taste and smell and alcohol drinking behaviors.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- To be eligible to participate in this study, an individual must meet all the following criteria:
- Individuals between 18 to 65 years of age. Although the age range of participants recruited in the NIAAA Natural History protocol is between 18-77 years, due to documented knowledge that taste and smell diminishes with age, we will limit age to this range.
- Individuals with a diagnosis of AUD (for the AUD cohort) OR without a diagnosis of AUD (for the non-AUD cohort) per clinician assessment
- Able to provide their own consent.
- Due to the extensive questionnaires (administered in English language only) that participants must complete independently, fluency in the English language is needed. Hence, participants must be able to read and understand English.
Exclusion criteria
- An individual who meets any of the following criteria will be excluded from participation in this study:
- Diagnosis by a medical professional of morbid obesity or BMI \> 40 or renal disease.
- Any history of chronic rhinitis, eating disorder, chronic upper respiratory infection, chronic allergic rhinitis, or nasal polyps in the last 6 months of screening, or current daily use of nasal sprays.
- Altered cranial nerves associated with taste and olfaction identified by neurological evaluation during physical exam (screening visit).
- Positive pregnancy test, currently pregnant or breastfeeding.
- Hypoglycemic drug intake.
- Currently using medications known to inhibit taste response (GLP1 agonists).
- Currently experiencing temporary change/loss of taste and/or smell (individual may be rescreened when symptoms resolve).
- Persistent loss of taste and/or smell due to COVID-19 or other reason.
- NIAAA employees/staff or subordinates/relatives/co-workers of NIAAA employees/staff or study investigators. fMRI Exclusion Criteria
- Claustrophobia
- Ferromagnetic metal in the cranial cavity or eye, e.g., aneurysm clip implanted neural stimulator, cochlear implant, ocular foreign body.
- Presence of implanted cardiac pacemaker or auto-defibrillator.
- Individuals with an insulin pump.
- Presence of an irremovable body piercing.
- Individuals who are pregnant or breastfeeding during screening, or who become pregnant during the study, will be excluded from participation due to risk of exposing the fetus to undue magnetic field hazards associated with MRI.
Where
- Bethesda, Maryland
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Data: ClinicalTrials.gov · synced Jun 16, 2026 · Source of record for eligibility and locations