Acute Effects of Artificial Sweeteners or Sugar on Hemodynamic and Metabolic Stress Responses

Study Overview
=================
Brief Summary
-----------------
This exploratory study aims at investigating the acute effects of artificially sweetened and sugar beverage consumption (as compared to water consumption) on acute hemodynamic and metabolic stress response.

Detailed Description
-----------------
This single-center study included five visits. The first two visits (screening and familiarization) allowed checking the eligibility of the volunteers. In case of inclusion, the subjects were assigned to a sequence of three experimental conditions (water, sugar and artificial sweeteners), in a randomized, crossover design. The experimental test was divided into 5 stages: a 90 minutes baseline period (t=0-90 min), a 30-min mental stress (MS; t=90-120 min), consisting in 5-min periods of Stroop's color word conflict test alternated with 5-min periods of mental arithmetic test. a 30-min MS recovery period (t=120-150), a 3-min cold pressure test (CPT) was carried out, aiming at immersing one volunteer's forearm in an ice water container at 3°C, 3) a 15-min CPT recovery period (t=120-150). 60 min after the beginning of the metabolic test, volunteers will drink 25 mL every 15 min, after 10-sec mouth rinsing, of either an artificially- or sugar-sweetened beverages or water (control). Hemodynamic stress responses will be measured by repeated blood pressure, heart rate and cardiac output. Repeated venous blood samples will allow to assess metabolic stress responses. Each condition (water, artificial sweeteners and sugar) will be preceded by a 2-day run-in period.

Official Title
-----------------
Acute Effects of Artificial Sweeteners' or Sugar's Ingestion on Hemodynamic and Metabolic Stress Response: An Exploratory, Randomized, Cross-over Trial in Healthy Young Women.

Conditions
-----------------
Normal Subjects

Intervention / Treatment
-----------------
* Other: Ingestion of artificially-sweetened beverages
* Other: Ingestion of sugar-sweetened beverages
* Other: Ingestion of water


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Healthy Caucasian Normal Body Mass Index (18.5 ≤BMI≤ 25 kg/m2) Monophasic oral contraceptive Exclusion Criteria: Hypertension (Blood pressure >140/90 mmHg) History or actual psychologic/cardiovascular troubles Anemia anamnesis Being Pregnant Weight < 50 kg Blood donation or participation to another study < 8 weeks Claustrophobia Consumption of sugar/artifically-sweetened beverages drinks > 5 dL/d Visual disturbances (daltonism) Low to moderate physical activity (> 4h/wk) Smoker and narcotic consumption Caffeine (> 400 mg/d) and/or alcohol (> 10g/d) consumption Medical treatment Weight variation > 3kg during the last month

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 40 Years

Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Basic Science
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Sugar<br>Effects of ingestion of sugar-sweetened beverages on acute stress response | Other: Ingestion of sugar-sweetened beverages<br>* From t=60 to the end of the metabolic test, volunteers will ingest 7 beverages containing sugar (25 mL / beverage) every 15 minutes after 10-sec mouth rinsing.<br>|
| Experimental: Artificial sweetener<br>Effects of ingestion of artificially-sweetened beverages on acute stress response | Other: Ingestion of artificially-sweetened beverages<br>* From t=60 to the end of the metabolic test, volunteers will ingest 7 beverages containing non nutritive sweeteners (25 mL / beverage) every 15 minutes after 10-sec mouth rinsing.<br>|
| Active Comparator: Water<br>Effects of ingestion of water on acute stress response | Other: Ingestion of water<br>* From t=60 to the end of the metabolic test, volunteers will ingest 7 water beverages (25 mL / beverage) every 15 minutes after 10-sec mouth rinsing.<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Hemodynamic changes | Hemodynamic changes elicited by stress will be assessed by means of systemic vascular resistance calculated as (blood flow):(mean arterial pressure, and expressed in arbitrary units | Differences observed between 90-min baseline and stress (30-min mental stress and 3-min cold pressure test) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in concentration of blood glucose | Blood glucose concentration will be measured in fasting conditions and during stress tests with the glucose oxidase method and expressed in mg/dl | Blood samples will be collected 30, 60, 75, 85, 95, 100, 110, 120, 125, 135, 145, 153, 158, and 163 minutes after the beginning of the test | 
| Changes in concentration of blood insulin | Blood insulin concentration will be measured by ELISA and expressed in mU/L | Blood samples will be collected 30, 60, 75, 85, 95, 100, 110, 120, 125, 135, 145, 153, 158, and 163 minutes after the beginning of the test | 
| Changes in blood non-esterified fatty acid concentration | Blood non-esterified fatty acid concentration will be measured by a colorimetric method and expressed in mmol/L | Blood samples will be collected 30, 60, 75, 85, 95, 100, 110, 120, 125, 135, 145, 153, 158, and 163 minutes after the beginning of the tes | 
| Metabolic changes | Metabolic changes elicited by stress will be continually monitored from respiratory gas exchanges by indirect calorimetry. | Differences observed between 90-min baseline and stress (30-min mental stress and 3-min cold pressure test) | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
sweeteners, sugar, stress response