Fiber Supplementation After Bariatric Surgery

Study Overview
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Brief Summary
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Test compliance and gastrointestinal tolerance of a 30-day dose of potato starch in bariatric patients, and determine if short chain fatty acids, specifically butyrate, increase in response to the dosages of potato starch.

Detailed Description
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Despite the successful weight loss associated with bariatric surgery, epidemiology studies have observed conflicting associations between bariatric surgery and incidence of colorectal cancer (CRC), potentially suggesting an increased risk of CRC post-surgery. The investigators have identified a potential mechanism between bariatric surgery and CRC via profiling dietary intake, gut microbiota colonization, and short-chain fatty acid (SCFA) production, including acetate, propionate, and butyrate. They have demonstrated a decrease in SCFA after bariatric surgery. As intestinal SCFAs inhibit colon cancer cell proliferation, these results may suggest a mechanism linking bariatric surgery, SCFA levels, and CRC. The objective of this protocol is to implement a 30-day fiber supplement, made from potato starch, as previous studies have successfully demonstrated that a resistant starch supplement increases intestinal SCFAs in healthy populations. The resistant starch supplement will be initiated 90-days post-bariatric surgery, which is when fiber supplements are tolerated. Fecal samples will be collected pre- and post-supplement and a targeted liquid chromatography/mass spectrometry platform will quantify levels of SCFAs. As SCFA levels have been associated with reduced hunger in other studies, the investigators will determine if hunger levels are altered in response to the supplement. The proposed study is described in the following aims: Specific Aim 1. Assess compliance and gastrointestinal tolerance of a 30-day dose of potato starch in bariatric patients. Specific Aim 2. Determine if short chain fatty acids, specifically butyrate, increase in response to the dosages of potato starch. Exploratory Aim. Determine if there are changes in dietary intake, appetite, and satiety in response to the dosages of potato starch.

Official Title
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Testing the Feasibility of Resistant Starch From Potatoes to Modify Short-chain Fatty Acid Levels After Bariatric Surgery

Conditions
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Bariatric Surgery Candidate

Intervention / Treatment
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* Dietary Supplement: Potato starch


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults ≥ 18 years Bariatric surgery at Dartmouth Medical Center Daily protein intake ≥ 60 grams Daily fluid intake ≥ 48 fl oz. Exclusion Criteria: > 550 lbs at bariatric surgery date. Allergies to potato starches. Surgical complications per bariatric team members Individuals who cannot speak and/or write in English.

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: Basic Science
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Potato Starch Supplement<br>Participants will consume a 24 grams of potato starch on Days 1-15 and 48 grams of potato starch on Days 16-30. | Dietary Supplement: Potato starch<br>* Participants will consume 24 grams (days 1-15) and 48 grams (days 16-30) of potato starch. Potato starch is a type 2 resistant starch that is available over the counter.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Gastrointestinal tolerance | Test gastrointestinal tolerance of a 30-day dose of potato starch in bariatric patients. Gastrointestinal tolerance will be measured using the GSRS survey (Svedlund et al, Digestive Diseases and Sciences, 1988). Statistics will use paired t-test. | 30 days | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Short-chain fatty acid | Test changes in short-chain fatty acid levels from stool samples after a 30-day dose of potato starch in bariatric patients. Statistics will use paired t-test. | 30 days |