AUTHORS: Aaron C. Miller, Linnea A. Polgreen, Elena M. Segre, Philip M. Polgreen
REVIEWER: Robyn Flipse, MS, MA, RDN
To model taste perceptions in a longitudinal or time-series fashion across the number of samples consumed
To determine if taste perceptions, in terms of the overall level and rate of decline, differ between normal-weight, overweight, and obese individuals
To analyze what effect, if any, the availability of nutritional information would have on taste perceptions
Decisions about what and how much to consume are driven, in part, by individual taste perceptions.
Diminishing marginal taste perception is the decline in taste perception an individual experiences from consuming one additional unit of a given food.
Sensory-specific satiety is the relationship between perceived taste and the quantity of food consumed, most often used to measure the difference between pre- and post-eating quantity.
If the rate at which marginal taste perceptions diminish differs among normal-weight, overweight, and obese adults, the quantification of satisfaction from food may help explain why some people eat more than others and represent a new obesity risk factor or phenotype.
290 adults between the ages 18-80 (80% female) were recruited; height and weight was measured with clothes and shoes on; BMI categories were defined using standard cutoffs.
Participants were randomized into two groups, “informed” and uninformed”, to observe the impact of nutritional information on taste perception.
Nutritional information for the chocolate samples was given to the “informed” group before the trial began.
Participants completed questionnaires on their taste perceptions with each piece of chocolate they consumed.
A pretzel was provided at the start and end of the trail to determine if the changes in marginal taste perception for chocolate were driven by simple changes in hunger or sensory-specific satiety.
Time-series regression was used to model perceived taste changes while controlling for participant characteristics.
For all three BMI categories average taste perceptions decreased as sample number consumed increased.
Taste perceptions of normal-weight and overweight participants followed a nearly identical downward trend distinct from the curve of obese participants.
Obese participants reported consistently greater taste perceptions than nonobese participants and their taste perceptions decreased at a slower rate.
There was no evidence that nutrition information about the chocolate had any impact on a participant’s initial taste perception or rate of decline.
Diminishing taste perceptions were not solely the result of satiation as the pretzels consumed at the beginning of the study were reported to provide the same taste perception as pretzels consumed at the end, despite substantial declines in hunger.
A consistent association was identified between taste from food, in this case chocolate, and BMI.
There were no significant differences in taste perceptions between normal and overweight participants.
Obese participants had initial taste perceptions that were greater than nonobese participants and their taste perception declined at a more gradual rate than nonobese participants.
Providing nutritional information did not affect marginal taste perception in any BMI group.
Points to Consider
Research has shown that people are more likely to overeat when more types of food are offered.
The diminishing taste perceptions seen here may be due to a type of sensory boredom from repeated consumption of the same item, consistent with research on sensory-specific satiety.
Other types of food (e.g. bitter or salty) may lead to different results.
Obese participants may need to consume a greater quantity of chocolate to experience a similar decline in taste perception to that of the nonobese participants.
Consuming chocolate (or other sweet foods) made with low-calorie sweeteners may help obese individuals achieve the same taste perception as lean and overweight individuals with the same quantity of food.
Robyn Flipse, MS, MA, RDN is a registered dietitian, cultural anthropologist and scientific advisor to the Calorie Control Council, whose 30+ year career includes maintaining a busy nutrition counseling practice, teaching food and nutrition courses at the university level, and authoring 2 popular diet books and numerous articles and blogs on health and fitness. Her ability to make sense out of confusing and sometimes controversial nutrition news has made her a frequent guest on major media outlets, including CNBC, FOX News and USA Today. Her passion is communicating practical nutrition information that empowers people to make the best food decisions they can in their everyday diets. Reach her on Twitter @EverydayRD and check out her blog The Everyday RD.
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