Metabolic Effects of a Caloric Restriction High/Low Glycemic Index Diet Plus Metformin in Overweight/Obese Subjects

Effects of a Caloric Restriction High/Low-glycemic Index Diets and in Combination With Metformin on Glucose Metabolism, Lipid Profile and Body Composition in Overweight/Obese Subjects

The prevalence of obesity and Type 2 diabetes has increased dramatically worldwide. Research on Glycemic Index (GI) diets has been largely developed, however the combination with metformin in humans was not investigated yet. We hypothesized that the low-GI diet in combination with metformin would elicit greater improvements on glucose metabolism, lipid profile and body composition on overweight or obese type 1 subjects. This study aims to evaluate the metabolic effects of the adoption of dietary advice to follow caloric restriction high/low GI diets, and low-GI diet associated with metformin on glucose metabolism, lipid profile and body composition on overweight or obese type 1 subjects.

Study Overview

• Status: Completed
• Conditions: Obesity
• Intervention / Treatment: Other: Glycemic Index Diets and Metformin hydrochloride

Detailed Description

All groups (Low/High-GI and Low-GI + Metformin) showed significant reduction in anthropometric parameters, but only Low-GI and Low-GI + Metformin groups have an improvement in body composition parameters. In addition, the Low-GI group achieved better results in metabolism of carbohydrates (glucose, insulin, Cederholm Index, and HOMA-β) and lipids (Chol, TAG, LDL-C, VLDL-C, and TC/HDL-c). These results show the benefits of Low-GI diet on metabolic parameters in overweight or obese type 1 subjects.

• Study Type: Interventional
• Enrollment (Actual): 41
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Brazil
  • DF
    • Brasília, DF, Brazil, 70910-900
      • School of Health Sciences, University of Brasília

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 50 years (ADULT)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Participants were adults (18-50 y), with body mass index (BMI) between 25-35 kg/m².
• Subjects with adequate glycemic and insulinemic response after oral glucose tolerance test: Hypocaloric diet with predominating high glycemic index foods;
• Subjects with altered glycemic response presented at the 120 min point either glycemia <140mg/dL and insulin level >40 µUI/ml: Hypocaloric diet with predominant low glycemic index foods;
• Subjects with impaired glucose tolerance presented at the 120 min point glycemia 140 - 199mg/dL and insulin >40 µUI/ml: Hypocaloric diet with predominant low glycemic index foods and metformin.

Exclusion Criteria:

• Smokers
• Pregnant or lactating
• Diagnosis of any metabolic diseases
• Were under medication and therapeutic diet, except oral contraceptive for women.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: NON_RANDOMIZED
• Interventional Model: PARALLEL
• Masking: NONE

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
OTHER: High Glycemic Index; Hypocaloric diet with predominating high glycemic index foods	Other: Glycemic Index Diets and Metformin hydrochloride; 1g of Metformin hydrochloride a day in High Glycemic Index Diet; Other Names: High Glycemic Index; Low Glycemic Index; High Glycemic Index plus Metformin
OTHER: Low Glycemic Index; Hypocaloric diet with predominant low glycemic index foods	Other: Glycemic Index Diets and Metformin hydrochloride; 1g of Metformin hydrochloride a day in High Glycemic Index Diet; Other Names: High Glycemic Index; Low Glycemic Index; High Glycemic Index plus Metformin
OTHER: Low Glycemic Index plus Metformin; Hypocaloric diet with predominant low glycemic index foods plus Metformin (1g/d)	Other: Glycemic Index Diets and Metformin hydrochloride; 1g of Metformin hydrochloride a day in High Glycemic Index Diet; Other Names: High Glycemic Index; Low Glycemic Index; High Glycemic Index plus Metformin

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Glucose Metabolism	2-hour oral glucose tolerance test (Glucose and Insulin levels), glucose and insulin IAUC, HbA1c, HOMA-IR, HOMA-β, and Cederholm Index.	0 and 4 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Lipid Profile	Cholesterol, TAG, LDL-C, VLDL-C, HDL-c, and Cholesterol/HDL-c ratio	0 and 4 months
Body Composition	Body weight, Height, Body mass index, Body fat mass, Free fat body mass, Waist circumference.	0 and 4 months
Clinical Assessment	FSH hormone, urea, creatinine, and uric acid urinary levels	0 and 4 months
Food Intake	Energy intake, macronutrients and fiber consumption	0 and 4 months

Collaborators and Investigators

• Sponsor: Caio Eduardo Gonçalves Reis
• Collaborators: University of Brasilia; Conselho Nacional de Desenvolvimento Científico e Tecnológico; Fund to support research of the Federal District, Brazil
• Investigators: Study Director: Teresa HM da Costa, Ph.D., University of Brasilia

Study record dates

Study Major Dates

• Study Start: October 1, 2004
• Primary Completion (ACTUAL): June 1, 2005
• Study Completion (ACTUAL): October 1, 2006

Study Registration Dates

• First Submitted: October 17, 2011
• First Submitted That Met QC Criteria: October 25, 2011
• First Posted (ESTIMATE): October 27, 2011

Study Record Updates

• Last Update Posted (ESTIMATE): October 27, 2011
• Last Update Submitted That Met QC Criteria: October 25, 2011
• Last Verified: October 1, 2011

More Information

Terms related to this study

• Keywords: Obesity; Cholesterol; Metformin; Glucose; Glycemic index; Caloric restriction; Energy intake; LDL Cholesterol; Lipid Metabolism; HDL Cholesterol
• Additional Relevant MeSH Terms: Body Weight; Overweight; Hypoglycemic Agents; Physiological Effects of Drugs; Metformin
• Other Study ID Numbers: Glycemic index and Metformin