Fizzy Drinks Study

Study Overview
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Brief Summary
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The objective of this study is to compare the effect of different levels of carbonation isocaloric beverages on glycemic response (using protocol based on standardized glycemic index testing methodology), gastric emptying and satiety. It is hypothesized that carbon dioxide will delay gastric emptying, and in turn, attenuate glycemic response and enhance satiety. The use of a non-nutrient (gas) in improving glycemic response and satiety would have important health implications for the beverage industry.

Detailed Description
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15-20 healthy subjects will be recruited for the study by means of advertisements, flyers and personal communications. A randomized, cross-over design experiment with three treatments will be carried out. Three different beverages will be prepared:- No carbonation (NC): Potable water + sugar- Low carbonation (LC): Potable water + sugar + little CO2- High carbonation (HC): Potable water + sugar+ high CO2. The outcome measures assessed will be glycemic response, gastric emptying and satiety. Glycemic response will be measured by taking capillary blood samples (<5ul) by fingerpricking with one-time use sterilized lancets. Gastric emptying will be assessed by ultrasonography methodology developed by Okabe et al, 2015. Satiety will be measured using electronic visual analogue scales assessing hunger, fullness, desire to eat, prospective consumption and thirst. In addition, participants will be asked to rate the level of effervescence of beverage, sweetness of beverage, amount of beverage consumed, as well as how pleasant the beverage was immediately after drinking of test beverage. Feelings of bloatedness will be assessed using electronic visual analogue scales administered at 0, 15, 30, 45, 60, 90,120 min from drinking of test beverage. At the end of the test session, ad libitum lunch will be served, and the amount of food and drinks consumed will be measured (by weight difference before and after serving).

Official Title
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The Effect of Different Levels of Carbonation in Drinks on Glycemic Response, Gastric Emptying, Satiety and Energy Intake

Conditions
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Glycemic Response, Gastric Emptying, Satiety

Intervention / Treatment
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* Other: No Carbonation
* Other: Low carbonation
* Other: High carbonation


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Healthy adult Aged between 21 - 40 years old BMI between 18.0-30.0 kg/m2 Blood pressure < 140/80 mmHg Fasting blood glucose < 6.0mmol/L Fasting blood glucose < 6.0mmol/L Exclusion Criteria: Are a smoker Have symptoms or medical history of gastrointestinal, cardiovascular, diabetes, cancer or other illnesses/diseases/conditions that could affect gastric motility and appetite Are on prescription medication Had a major medical or surgical event requiring hospitalization within the preceding 3 months. Are taking part in other clinical trials concurrently Are taking part in sports at competitive/endurance levels Have a score equal or greater than 3.7 for restrained eating in Dutch Eating Behaviour Questionnaire. Have special dietary requirements or food allergies.

Ages Eligible for Study
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Minimum Age: 21 Years
Maximum Age: 40 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

Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: No carbonation (control)<br>No carbonation (NC, control): Potable water + sugar | Other: No Carbonation<br>* 500 ml of beverage consisting of water + 10% glucose and no carbonation<br>|
| Active Comparator: Low carbonation<br>Low carbonation (LC): Potable water + sugar + little CO2 | Other: Low carbonation<br>* 500 ml of beverage consisting of water + 10% glucose and low carbonation<br>|
| Active Comparator: High carbonation<br>High carbonation (HC): Potable water + sugar+ high CO2 | Other: High carbonation<br>* 500 ml of beverage consisting of water + 10% glucose and high carbonation<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in blood glucose concentrations in capillary blood using Hemocue | Capillary blood glucose will be assessed at 0, 15, 30, 45, 60, 90, 120 minutes using a Hemocue system (HemoCue Glucose 201 RT Systems) | 0, 15, 30, 45, 60, 90 and 120 min after drinking test beverage | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in cross sectional area of antrum imaged using ultrasound | Cross sectional area of antrum will be assessed at 0, 15, 30, 45, 60, 90, 120 minutes using ultrasonography. | 0, 5, 10, 20, 30, 40, 50, 60, 90, 120 after drinking test beverage | 
| Satiety | Appetite ratings will be collected at 0, 15, 30, 45, 60, 90, 120 minutes after drinking test beverage using a previously validated visual analog scales [Flint, A., A. Raben, J. E. Blundell and A. Astrup (2000). Reproducibility, power and validity of visual analogue scales in assessment of appetite sensations in single test meal studies. International Journal of Obesity 24(1): 38-48] | 0, 15, 30, 45, 60, 90 and 120 min after drinking test beverage | 
| Amount of food consumed | Ad-libitum lunch will be provided 2.5 hours after beverage consumption. The weight of the foods (g) will be taken before and after consumption, and the difference will be taken to measure the amount of food consumed (g). | 2.5 hr subsequent to beverage consumption | 
| Energy intake | Ad-libitum lunch will be provided 2.5 hours after beverage consumption. The energy intake will be calculated from the amount of food consumed (see Outcome 4), as well as the energy content per weight (read off from the nutritional information panel provided on the packaging) to calculate the energy intake (kcal). | 2.5 hr subsequent to beverage consumption |