To Compare the Effects of Non-nutritive Sweeteners Intake in Woman With Insulin Resistance

Protocol The experimental design was developed 3 times. Each intervention was performed separately for a minimum period of 7 days out and a maximum of 14 days, depending on the availability of the experimental subjects. Cross treatment design (crossover) each women serves as its own control The first intervention corresponded to the control group, in order to maintain the ignorance of the type of sweetener they were receiving, between day 7 or maximum 14 days post-intervention the order of the test of the NNS was reversed. Therefore, during the second or third intervention they were given to drink water with D-tagatose or stevia respectively. For each intervention a check list was followed.

Subjects were asked to maintain their normal diet between study days and abstain from strenuous exercise and alcohol intake for 24 hours before each evaluation. The subjects attended with an 8-hour fast, without having ingested medication, to the sampling room of the Pharmacy Faculty, University of Valparaís. The study was only begun if they had a capillary glycemia <100%, measured through a glucometer.

Then, they were asked to answer the analogue visual scale (VAS) questionnaire and an intravenous catheter was installed in the antecubital vein to take the blood samples at "time -10". Immediately, they were given to drink 60 ml of water or 60 ml of water with 5000 mg of D-tagatose or an equivalent volume with 15,3 mg of stevia (steviol glycosides), which they had to consume in less than 2 minutes.

After 10 minutes, at "time 0" immediately after the second blood sample, the individuals consumed a 75-gram oral glucose tolerance test (OGTT).

The following blood samples were taken at times 30, 60, 90, 120 and 180 minutes after "time 0". In total, 28 ml of blood was extracted, in each time the glycemia and C-peptide were determined (4 ml was taken at a time).

In addition, VAS questionnaires were applied every 30 minutes, from "time -10" to 180 minutes for appetite determinations.

After completing the extraction of blood samples at 180 minutes and removing the intravenous catheter, the subjects were offered a meal for 30 minutes, which consisted of a variety of foods of high acceptability, previously weighed and fractionated.

Statistic analysis The normal distribution of the variables was determined by the Shapiro-Wilk test. The natural logarithm was applied to the parameters without normal distribution. The variables were expressed as mean ± standard deviation or median plus interquartile interval (Q1-Q3). The statistical significance between the differences in plasma glucose concentrations, area under the curve (AUC) of glycaemia, energy intake and macronutrients by treatment (preload water, D-tagatose and stevia), was evaluated through Anova of repeated samples . To analyze the differences between plasma concentrations and AUC of C-peptide and glycaemia per treatment (preload water, D-tagatose and stevia), Friedman's test was used, followed by Wilcoxon and adjusted by Bonferroni.

To identify the relationships between glycemic responses and intake of food at will (energy intake and macronutrients by treatment, preload water, D-tagatose and stevia), the Pearson correlation factor was used, in contrast to C-peptide response and the visual analogue scale (VAS) and food intake at will per treatment Spearman's correlation factor was used.

The statistical analysis was performed with the SPSS 20.0 computer program (SPSS Inc., Chicago Illinois). A p <0.05 was considered statistically significant for all the analyzes.