Impact of No-carrageenan Diet on Glucose Tolerance in Prediabetes

Study Overview
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Brief Summary
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Participants will be randomly assigned to either regular or no-carrageenan prepared diets to determine whether the no-carrageenan leads to improvement in glucose tolerance. Hemoglobin A1c is the primary outcome measure.

Detailed Description
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Subjects will be randomly assigned to a diet. They will at onset have hemoglobin A1c values between 5.7% and 6.4%. Baseline glucose tolerance test will be performed, as well as measures of inflammation and fecal microbiome. Interim tests will be performed at six weeks. Subjects will participate for 12 weeks, at which time they will be re-evaluated.

Official Title
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Impact of no Carrageenan Diet on Glucose Tolerance in Prediabetes

Conditions
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Prediabetes

Intervention / Treatment
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* Other: No-carrageenan diet
* Other: Regular Diet


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: per diabetes, ability to follow diet and study procedures Exclusion Criteria: on any medications that affect glucose, medical conditions or allergies that affect adherence to study diet, pregnancy

Ages Eligible for Study
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Minimum Age: 18 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: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Placebo Comparator: Regular diet<br>Meals and snacks will contain carrageenan in the amount consumed in the typical daily diet and will be selected by the study dietician and distributed to study subjects randomized to the regular diet study arm. | Other: Regular Diet<br>* Diet of food items that have carrageenan as selected by study dietician<br>* Other names: Carrageenan-containing diet;|
| Experimental: No-carrageenan diet<br>No-carrageenan diet will be composed of meals and snacks selected by the study dietician and distributed to study participants who are randomized to the no-carrageenan diet study arm. | Other: No-carrageenan diet<br>* Diet of food items that have no carrageenan as selected by study dietician.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in hemoglobin A1c | Measurements performed after 12 weeks of dietary intervention | baseline, 12 weeks | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in serum Interleukin-8 | Impact of diet on serum Interleukin-8 | baseline, 12 weeks | 
| Impact on glucose tolerance test | perform repeat oral glucose tolerance test after 12 weeks of dietary intervention | 12 weeks | 
| Impact on insulin level | determine effect of dietary intervention on insulin level at the time of glucose tolerance test | 12 weeks | 
| Change in leukocyte subsets | determine if there is change in distribution of leukocyte subsets from blood samples of study participants | baseline, 12 weeks | 
| Change in Tumor Necrosis Factor-alpha in serum | determine if there is change in circulating TNF-alpha in blood samples | baseline, 12 weeks | 
| Change in insulin signaling pathway | determine if there are changes in activation of intermediates in insulin signaling pathway in circulating leukocytes following dietary intervention | baseline, 12 weeks |