Variations in Marginal Taste Perception by Body Mass Index Classification: A Randomized Controlled Trial

Abstract

Background: The propensity to overeat may, in part, be a function of the satisfaction derived from eating. If levels of satisfaction derived from food differ among normal-weight, overweight, and obese adults, the quantification of satisfaction from food may help explain why some people eat more than others.

Objective: To quantify the satisfaction obtained from eating one specific food, chocolate, by measuring taste perception as normal-weight, overweight, and obese participants consumed additional pieces of chocolate. To measure the effect of nutritional information on chocolate consumption.

Design: Randomized, controlled trial.

Participants/setting: We analyzed data on 290 adults; 161 had a body mass index (BMI) that was considered normal (<25), 78 had a BMI considered overweight (≥25 and <30), and 51 had a BMI considered obese (≥30).

Intervention: Participants were given samples of chocolate, one at a time, until they chose to stop eating. With each sample, participants were given a questionnaire. Half of the study participants were randomly selected to receive nutritional information (n=150).

Main outcome measures: Perceived taste for each sample.

Statistical analyses performed: We used time-series-regression to model perceived taste changes while controlling for participant characteristics.

Results: Study participants consumed between 2 and 51 pieces of chocolate with a mean of 12.1 pieces. Average taste perception decreased with each piece. We found no significant difference in taste perceptions between normal- and overweight participants. However, obese participants had higher levels of initial taste perception than normal- and overweight participants (P=0.02). Also, obese participants reported taste perceptions that declined at a more gradual rate than normal- and overweight participants (P<0.01). Self-reported hunger, prior to the study, affected taste perception, but providing nutritional information did not.

Conclusions: Obese participants started with higher levels of perceived taste and also experienced slower rates of decline than did normal-weight and overweight individuals.

Keywords: Chocolate; Food labeling; Obesity; Preferences.