Clinical trial NCT01651221: Repeated Food Exposure Via the Olfactory and Gustatory Systems
Official title: Repeated Food Exposure Via the Olfactory and Gustatory Systems
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Habituation
Keywords: gustatory response
olfactory response
Lead sponsor: The University of Tennessee, Knoxville
Sponsor class: OTHER
First posted: 2012-07-26
Enrollment: 27
Sex: FEMALE
Minimum age (years): 18
Maximum age (years): 30
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: SINGLE_GROUP
Primary purpose: OTHER

Brief summary: Increasing exposure to a single orosensory cue without ingestion of additional energy may promote an increased rate of habituation, more rapid satiation, and reduced intake. This exposure can occur via smell (olfactory) and taste (gustatory) systems.It is not clear if repeated exposure via the combined olfactory and gustatory systems increases the rate of habituation more so than repeated exposure through one of these systems. Thus, the purpose of this investigation is to examine the amount of salivation occurring in 12 trials of exposure to a food via the olfactory, gustatory, and combined olfactory and gustatory systems. The primary dependent variable will be the amount of salivation in the 12 trials. It is hypothesized that a more rapid decrease in salivation will occur across trials in the combined olfactory and gustatory exposure as compared to the other two conditions, indicating a more rapid rate of habituation.

Detailed description: Approximately two of every three adults in the U.S. are overweight or obese. The high prevalence of overweight/obesity negatively affects the health of the population, as obese individuals are at increased risk for developing several chronic diseases.

Successful control of body weight depends on effectively regulating eating. Satiation, the process by which an eating bout ends, assists with eating regulation, and factors that quicken the onset of satiation may aid with decreasing intake. One factor believed to influence satiation is the rate of decrease in consummatory response (habituation) to repeated presentations of food orosensory cues. Habituation is a basic form of learning, in which behavioral and physiological responses decrease in response to repeated presentations of a stimulus, with the decrease in response unrelated to sensory adaptation/fatigue or motor fatigue.

In one condition, participants will smell lemon and lime across 12 trials (olfactory exposure), in another condition participants will taste the juices across 12 trials (gustatory exposure), and in the last condition participants will smell and taste the juices across 12 trials (olfactory + gustatory exposure). The primary dependent variable will be the amount of salivation in the 12 trials. It is hypothesized that a more rapid decrease in salivation will occur across trials in the combined olfactory and gustatory exposure as compared to the other two conditions, indicating a more rapid rate of habituation

Eligibility criteria: Inclusion Criteria:

* Dietary restraint scores of less than or equal to 12 on the Three Factor -
* Eating Questionnaire-Cognitive Restraint scale.
* Have a body mass index (BMI) between 18.5 and 24.9.

Exclusion Criteria:

* Are taking medications or having an illness which might influence salivation, smell, and taste (i.e. upper respiratory illness, methylphenidate, atropine, Benadryl, Elavil, etc)
* Are currently dieting
* Are a binge eater
* Do not at least moderately like lemon or lime flavor scoring \< 50 on a 100 mm visual analogue scale
* Are a regular smoker
* Have any dietary restrictions that will inhibit participation including food allergies

Primary outcomes:
measure: Amount of Salivation
timeFrame: 12 trials (90 minutes)
Secondary outcomes:
Other outcomes:
Locations:
city: Knoxville
country: United States
facility: Healthy Eating and Activity Lab, University of Tennessee
state: Tennessee
Study officials:
affiliation: University of Tennessee
name: Hollie A Raynor, PhD RD LDN
role: PRINCIPAL_INVESTIGATOR
References: