Effect of Meal Frequency on Glycemic Control of People at High Risk or Diagnosed With Diabetes

The Effects of Meal Frequency on Glucose, Insulin, and Insulin Sensitivity in Women With Polycystic Ovary Syndrome (PCOS), People at High Risk for Developing Type 2 Diabetes and People With Type 2 Diabetes

This study investigated any potential associations between two isocaloric diets with different meal frequency (3 meals versus 6 meals) and glycemic control in people at high diabetes risk (lean and overweight/obese women with PCOS, individuals with hyperinsulinemia, individuals with impaired glucose tolerance) and diagnosed with diabetes.

Study Overview

• Status: Completed
• Conditions: Hyperglycemia; Hyperinsulinism; Impaired Glucose Tolerance; Insulin Sensitivity; Poor Glycemic Control
• Intervention / Treatment: Other: Isocaloric diet with 3 meals; Other: Isocaloric diet with 6 meals

Detailed Description

The effect of meal frequency on diabetes risk markers (e.g. glucose and insulin metabolism) has been studied in several studies so far, both in healthy individuals and in individuals being at risk for diabetes mellitus, with or without concurrent weight loss. In addition, few studies have investigated the effect of different meal frequency on glycemic control in patients with diabetes mellitus under conditions of weight maintenance. However, the results regarding the ideal number of meals remain controversial.

To our best knowledge, there is no study available that has investigated the effect of meal frequency on glucose and insulin metabolism in lean and obese women with PCOS, in lean and obese individuals with hyperinsulinemia and impaired glucose tolerance, and in obese individuals with type 2 diabetes, independently of weight loss.

• Study Type: Interventional
• Enrollment (Actual): 110
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: ADULT; OLDER_ADULT; CHILD
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• The presence of type 2 diabetes was defined according to the current diagnostic criteria: (a) HbA1c ≥ 6.5%, (b) fasting plasma glucose ≥126 mg/dl (7.0 mmol/l). (c) 2-h plasma glucose ≥ 200 mg/dl (11.1 mmol/l) during an oral glucose tolerance test (OGTT), using a glucose load containing the equivalent of 75 g anhydrous glucose dissolved in water, or (d) a random plasma glucose ≥ 200 mg/dl (11.1 mmol/l) in patients with classic symptoms of hyperglycemia or hyperglycemic crisis.
• PCOS was defined according to the Rotterdam criteria (Rotterdam 2004) which include the presence of two or more of the following features: chronic oligoovulation or anovulation (fewer than six menstrual periods in the previous year), androgen excess (serum total testosterone >70 mg/dl) and polycystic ovaries.

Exclusion Criteria:

• Insulin sensitizers, i.e. metformin, contraceptives, steroids or any medications known to affect glucose, insulin or reproductive hormones for at least the last 6 months.
• Serious health problems like cardiovascular, liver or kidney diseases.
• Volunteers who were on diet, using medications affecting body mass or who had experienced a change in body weight ≥ 4.5 kg or a change in physical activity within the 6 months preceding the study onset were excluded.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: TREATMENT
• Allocation: RANDOMIZED
• Interventional Model: CROSSOVER
• Masking: NONE

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
EXPERIMENTAL: Polycystic Ovary Syndrome; 40 women with PCOS followed one of two isocaloric weight maintenance diets (isocaloric diet with 3 meals or isocaloric diet with 6 meals), tailored to individual energy needs, with the same macronutrient composition (40% carbohydrates, 25% protein, 35% fat). The energy and carbohydrate contribution for the 3 meals' diet was 20% at breakfast, 50% at lunch, 30% at dinner, whereas for the 6 meals' diet was 20% at breakfast, 10% at morning snack, 30% at lunch, 10% at afternoon snack, 20% at dinner, 10% at before bedtime snack. Each intervention lasted 12 weeks and there was no wash out period.	Other: Isocaloric diet with 3 meals; Isocaloric diet with 3 meals in order to maintain volunteers' weight, tailored to individual energy needs, with the same macronutrient composition. The volunteers were free to choose the foods they used to consume before. However, in order to assist them to adapt to the different meal frequency, individualized instructions were given to all volunteers before their entry to the study. An example of a 7-day diet menu was prescribed for both diet programs and analytical food exchange lists of different food groups were also provided.; Other: Isocaloric diet with 6 meals; Isocaloric diet with 6 meals in order to maintain volunteers' weight, tailored to individual energy needs, with the same macronutrient composition. The volunteers were free to choose the foods they used to consume before. However, in order to assist them to adapt to the different meal frequency, individualized instructions were given to all volunteers before their entry to the study. An example of a 7-day diet menu was prescribed for both diet programs and analytical food exchange lists of different food groups were also provided.
EXPERIMENTAL: Impaired Glucose Tolerance; 35 individuals with Impaired Glucose Tolerance (IGT) followed one of two isocaloric weight maintenance diets (isocaloric diet with 3 meals or isocaloric diet with 6 meals), tailored to individual energy needs, with the same macronutrient composition (45% carbohydrates, 20% protein, 35% fat). The energy and carbohydrate contribution for the 3 meals' diet was 20% at breakfast, 50% at lunch, 30% at dinner, whereas for the 6 meals' diet was 20% at breakfast, 10% at morning snack, 30% at lunch, 10% at afternoon snack, 20% at dinner, 10% at before bedtime snack. Each intervention lasted 12 weeks and there was no wash out period.	Other: Isocaloric diet with 3 meals; Isocaloric diet with 3 meals in order to maintain volunteers' weight, tailored to individual energy needs, with the same macronutrient composition. The volunteers were free to choose the foods they used to consume before. However, in order to assist them to adapt to the different meal frequency, individualized instructions were given to all volunteers before their entry to the study. An example of a 7-day diet menu was prescribed for both diet programs and analytical food exchange lists of different food groups were also provided.; Other: Isocaloric diet with 6 meals; Isocaloric diet with 6 meals in order to maintain volunteers' weight, tailored to individual energy needs, with the same macronutrient composition. The volunteers were free to choose the foods they used to consume before. However, in order to assist them to adapt to the different meal frequency, individualized instructions were given to all volunteers before their entry to the study. An example of a 7-day diet menu was prescribed for both diet programs and analytical food exchange lists of different food groups were also provided.
EXPERIMENTAL: Type 2 Diabetes; 12 individuals diagnosed with type 2 diabetes followed one of two isocaloric weight maintenance diets (isocaloric diet with 3 meals or isocaloric diet with 6 meals), tailored to individual energy needs, with the same macronutrient composition (45% carbohydrates, 20% protein, 35% fat). The energy and carbohydrate contribution for the 3 meals' diet was 20% at breakfast, 50% at lunch, 30% at dinner, whereas for the 6 meals' diet was 20% at breakfast, 10% at morning snack, 30% at lunch, 10% at afternoon snack, 20% at dinner, 10% at before bedtime snack. Each intervention lasted 12 weeks and there was no wash out period.	Other: Isocaloric diet with 3 meals; Isocaloric diet with 3 meals in order to maintain volunteers' weight, tailored to individual energy needs, with the same macronutrient composition. The volunteers were free to choose the foods they used to consume before. However, in order to assist them to adapt to the different meal frequency, individualized instructions were given to all volunteers before their entry to the study. An example of a 7-day diet menu was prescribed for both diet programs and analytical food exchange lists of different food groups were also provided.; Other: Isocaloric diet with 6 meals; Isocaloric diet with 6 meals in order to maintain volunteers' weight, tailored to individual energy needs, with the same macronutrient composition. The volunteers were free to choose the foods they used to consume before. However, in order to assist them to adapt to the different meal frequency, individualized instructions were given to all volunteers before their entry to the study. An example of a 7-day diet menu was prescribed for both diet programs and analytical food exchange lists of different food groups were also provided.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Serum levels of glucose	Clinically useful change in serum glucose, defined as the restoration of glucose within normal limits during the 2-hour oral glucose tolerance test.	6 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Serum levels of insulin	Clinically useful change in serum insulin, defined as the restoration of insulin within normal limits during the 2-hour oral glucose tolerance test. Improved insulin sensitivity.	6 months
HbA1c	Clinically useful change in HbA1c.	6 months
Lipidemic profile	Normal serum levels of cholesterol, High Density Lipoprotein (HDL), Low Density Lipoprotein (LDL) and Triglycerides.	6 months

Collaborators and Investigators

• Sponsor: Meropi Kontogianni
• Collaborators: National and Kapodistrian University of Athens; Agricultural University of Athens
• Investigators: Study Director: Aimilia Papakonstantinou, PhD, Agricultural University of Athens; Principal Investigator: Meropi Kontogianni, PhD, Harokopio University of Athens

Study record dates

Study Major Dates

• Study Start: October 1, 2011
• Primary Completion (ACTUAL): September 1, 2013
• Study Completion (ACTUAL): September 1, 2013

Study Registration Dates

• First Submitted: September 22, 2014
• First Submitted That Met QC Criteria: September 23, 2014
• First Posted (ESTIMATE): September 25, 2014

Study Record Updates

• Last Update Posted (ACTUAL): October 4, 2017
• Last Update Submitted That Met QC Criteria: October 2, 2017
• Last Verified: October 1, 2017

More Information

Terms related to this study

• Keywords: Type 2 Diabetes; Polycystic ovary syndrome; Hyperinsulinemia; Meal frequency
• Additional Relevant MeSH Terms: Glucose Metabolism Disorders; Metabolic Diseases; Immune System Diseases; Neoplasms; Endocrine System Diseases; Ovarian Cysts; Cysts; Ovarian Diseases; Adnexal Diseases; Gonadal Disorders; Hyperglycemia; Hypersensitivity; Polycystic Ovary Syndrome; Glucose Intolerance; Insulin Resistance; Hyperinsulinism
• Other Study ID Numbers: 8062 (CTEP); HUA (OTHER: Harokopio University)