Fiber Supplementation After Bariatric Surgery

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.

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.