The Effect of Dietary Sugar Consumption on Sweet Taste Perception

Study Overview
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Brief Summary
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The purpose of the study is to determine how reducing the amount of simple sugars in the diet affects sweet taste perception. Healthy adult subjects will be assigned to either follow their usual diet, or to replace sugar calories with fats or starch. The investigators hypothesize that eating less sugar will: cause foods and drinks with a given amount of sugar to taste sweeter cause people to prefer lower levels of sugar in foods and drinks

Official Title
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The Effect of Dietary Sugar Consumption on Sweet Taste Perception

Conditions
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Sweet Taste Perception

Intervention / Treatment
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* Other: Low sugar diet
* Other: Sham diet manipulation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Good general heath (by self report) Consume at least 2 sugar-containing soft drinks/day on average) Able to control diet (select their own foods) Exclusion Criteria: Major illness of any kind within the last six months, or any chronic illness Daily use of medication, except for birth control, vitamins, and aspirin Regularly consume non-nutritive sweeteners Pregnant women Gained or lost 10% or more of their body weight in the last 3 months

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 60 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Sham Comparator: No change in dietary sugar levels<br>Group met with a dietician as often as the control group to discuss diet, but the dietician gave them advice geared toward no change in dietary sugar levels | Other: Sham diet manipulation<br>* Subjects in the control group will meet with a dietician and discuss diet records, but the dietician will not instruct the control subjects to reduce the number of calories from simple sugars in the diet<br>|
| Experimental: Low sugar group<br>Subjects met with a dietician who discussed diet records. After the first month (baseline, regular diet), the dietician made suggestions geared toward reducing calories from simple sugars by 40%. This will be achieved by replacing sugar calories with complex carbohydrates and fats, while maintaining energy balance (same number of calories as the baseline month). | Other: Low sugar diet<br>* All subjects followed their usual diet during month 1. For months 2-4: sham diet intervention for the control group, 40% reduction in sugar calories for the experimental group. All subjects were allowed to chose any diet they wished during month 5.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Sweet Taste Intensity over Five Months | Subjects rated the sweetness of pudding and beverage samples that varied in sucrose concentration during each study month to determine how perception changes over time with diet manipulations | Monthly (for five months) | 
| Change in Pleasantness Over Five Months | Subjects rated hedonic value (degree to which the sample was pleasant) for model pudding and beverages that differed in concentration of sucrose once each month over five months to determine how perception changed over time with the diet manipulation | Monthly (five month participation duration total) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sucrose detection thresholds | Test of the minimum concentration of sucrose solution that subjects can discriminate from water. Forced-choice, ascending concentration method. | Every month (for five months) | 
| Body mass index | BMI, calculated based on weight and height. This was measured both to balance treatment groups and to ensure that assigned diets maintained adequate energy balance (no change in BMI over the study was the ideal outcome for all groups) | Every month (five months total) | 
| Diet records | Subject reported in detail the types and quantities of the foods and beverages they ate. | Every month (five month total) |