Nutritional Prevention of Diabetes Mellitus Type 2

Study Overview
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Brief Summary
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This study investigates the influence of red meat and fibers on glucose metabolism and body fat composition in subjects at increased risk for type 2 diabetes.

Detailed Description
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The epidemiologic evidence for increased red meat intake and decreased fiber intake as risk factors for T2D is solid. However, few intervention studies have been performed in order to investigate the role of whole-grain intake or the consumption of red meat in glycemic control and prevention of diabetes, yielding contradicting results. Thus, in order to prove causality, further identify potential underlying mechanisms and be able to improve lifestyle modification programs, we performed a randomized, controlled intervention study over six months. The participants are individuals at increased risk for tyoe 2 diabetes. They were randomised to 3 interventions groups: 1) caloric restriction of 400 kcal/day (control group), 2) caloric restriction plus no red meat consumption 3) caloric restriction and increase in fiber intake. Subjects where thoroughly phenotyped by anthropometric parameters, oral glucose tolerance tests, and MRI measurements of body fat composition and iron content in the liver. In this study, we want to compare the effectiveness of reduced caloric intake only versus reduced caloric intake with an additional modification of diet composition in terms of red meat and fiber consumption.

Official Title
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Identification of Factors Predicting the Success of a Nutritional Intervention to Decrease the Risk of Type 2 Diabetes

Conditions
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Type 2 Diabetes Mellitus, Nutritional and Metabolic Diseases, Liver Fat, Insulin Sensitivity

Intervention / Treatment
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* Behavioral: Caloric restriction
* Behavioral: no red meat
* Behavioral: Increased fiber intake


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Individuals at a high risk for Type 2 diabetes: positive family history of type 2 diabetes, presence of metabolic syndrome, body mass index (BMI) > 27 kg/m2, diagnosis of impaired glucose tolerance (IGT) previous diagnosis of gestational diabetes diabetes Exclusion Criteria: Main exclusion criteria diagnosis of type 1 or 2 diabetes mellitus BMI >45 kg/m² presence of serious illness such as cardiovascular, malignant or psychiatric disease.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 75 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Caloric restriction (control)<br>daily reduction of caloric intake aimed at 400 kcal/day | Behavioral: Caloric restriction<br>* After the baseline measurements individuals underwent dietary counseling and had 6 sessions with a dietician (after, 1,4,8,12 16 and 20 weeks).<br>|
| Active Comparator: No red meat<br>daily reduction of caloric intake aimed at 400 kcal/day plus no red meat intake | Behavioral: no red meat<br>* After the baseline measurements individuals underwent dietary counseling and had 6 sessions with a dietician (after, 1,4,8,12 16 and 20 weeks).<br>|
| Active Comparator: Increased fiber intake<br>daily reduction of caloric intake aimed at 400 kcal/day plus increased fiber intake (aim: 40gr/day) | Behavioral: Increased fiber intake<br>* After the baseline measurements individuals underwent dietary counseling and had 6 sessions with a dietician (after, 1,4,8,12 16 and 20 weeks).<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| change in glucose metabolism | glucose metabolism measured during the oral glucose tolerance test (OGTT) | baseline and six months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Insulin secretion | Disposition index (insulin sensitivity (Matsuda) x insulinogenic index (IGI)) | baseline and six months | 
| liver fat | measured by magnetic resonance spectroscopy | baseline and six months | 
| liver iron content | measured by magnetic resonance imaging | baseline and six months | 
| body composition | measured by magnetic resonance imaging | baseline and six months |