OPTIFIT-Optimal Fiber Trial for Diabetes Prevention

Not Applicable

Completed

• Conditions: Glucose Metabolism Disorders; Nutrition Disorders; Diabetes; Obesity; Body Weight; Metabolic Diseases; Overweight; Metabolic Syndrome x
• Interventions: Dietary Supplement: Placebo; Dietary Supplement: Fiber

• Registration Number: NCT01681173
• Lead Sponsor: German Institute of Human Nutrition

Brief Summary

High intake of insoluble fiber is strongly associated with a reduced incidence of diabetes and cardiovascular events in prospective observation studies. Our primary objective is to compare a life style diabetes prevention program(PRAEDIAS) with and without added insoluble fibers in its effectiveness to prevent incident diabetes type 2 in high risk individuals with impaired glucose tolerance. Subjects with IGT not willing to participate in the intervention will be used as independent controls. Secondary aims are to identify mechanisms of action with regard to body composition, anti-inflammatory and metabolic effects of fibers. We propose a randomized, prospective intervention study. The results will be of general relevance for guidance of fiber intake in the population and will help the food industry to design healthy high fiber foods. Fiber can be added at low cost to numerous foods. Increased fiber intake may therefore provide a simple non-cognitive prevention strategy effective at the population level.

Detailed Description

The overall objective is to investigate whether insoluble fibers added to standard nutrition can reduce the progression of impairment of glucose metabolism in a high risk population with impaired glucose metabolism. Large prospective cohort studies clearly show that mainly insoluble cereal fiber from whole grains is associated with reduced risk of type 2 diabetes and cardiovascular disease. However, there is a lack of evidence from prospective intervention studies targeted to evaluate the potential of dietary fibers to reduce diabetes and cardiovascular disease as recently stated by the Cochrane Foundation. Dietary fiber intake is generally much lower than currently recommended, which may in part be related to side effects of whole grain nutrients and their gustatory properties. Intestinally uncomfortable effects are at least partly related to fermentation which is much less induced by insoluble non-fermentable fibers than by soluble fermentable fibers. The prospective demonstration of beneficial effects of insoluble fibers in preventing diabetes type 2 will allow detailed nutritional recommendations. This may serve to support the consumption of metabolically beneficial constituents of fiber-rich diets and help to increase fiber intake by high fiber natural nutrients or everyday nutrients enriched in insoluble natural fibers.

Study Timeline

• Study Start: 2010-05
• Study First Submitted: 2012-09-05
• Study First Submitted QC: 2012-09-05
• Study First Posted: 2012-09-07
• Primary Completion: 2014-12
• Study Completion: 2014-12
• Status Verified: 2015-02
• Last Update Submitted: 2015-02-04
• Last Update Posted: 2015-02-05

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 200

Inclusion Criteria

• Impaired glucose tolerance
• Age>18years old
• both gender

Exclusion Criteria

• Diabetes type 1 and type 2
• chronic or malignant disease
• Intake of metabolic influence drugs
• Food allergies, fiber intolerance

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Placebo drink	Placebo	Placebo drink, BID
Drink enriched in fibers	Fiber	7,5g enriched fiber drinks, BID

Primary Outcome Measures

Name	Time	Method
Change of 2h-postprandial blood glucose from IGT to diabetes mellitus type 2 or normal glucose tolerance (NGT)	0, 12, 24 months	Change of the glucose metabolism (OGTT)

Secondary Outcome Measures

Name	Time	Method
Change of insulin sensitivity	0, 12, 24 months	Measurement by HOMA and OGIS from the OGTT
Change of insulin secretion	0, 12, 24 months	Measurement by the OGTT
Assessment of cognitive performance	0, 12, 24 months
Development of indices for the prediction of fat mass	0, 12, 24 months	Change of fat fraction in liver, abdominal and in the total body fat measuring by MRI/H1-spectroscopy
Determination of gene expression in adipose tissue	0, 12, 24 month	Determination of inflammatory and other transcripts in sc adipose tissue in a fat biopsy.
Expression of inflammatory markers in blood	0, 6, 12, 18, 24 months	CRP, leukocytes, adipocytokines
Biometric data	0, 6, 12, 18, 24 months	Nutritional impact of blood pressure, anthropometry (body weight and body composition)

Trial Locations

Locations (2)

Charite University; 🇩🇪 Berlin, Germany

German Instiute of Human Nutrition; 🇩🇪 Potsdam-Rehbruecke, Nuthetal, Germany