DASH INtervention to INvestigate the Gut

Not Applicable

Recruiting

• Conditions: Microbiota; Cancer
• Interventions: Behavioral: standard American diet; Behavioral: DASH Diet

• Registration Number: NCT04538482
• Lead Sponsor: H. Lee Moffitt Cancer Center and Research Institute

Brief Summary

The study investigators will recruit a generally healthy sample of 112 black and white adults from Birmingham, AL to participate in a 28-day randomized, controlled feeding study. Participants will be randomized to receive either the DASH diet or a standard American diet. All meals will be provided by the study. Fecal samples will be collected at multiple time points before, during, and after the dietary intervention and will be analyzed using PCR to amplify the V4 region of the 16S rRNA gene and to sequence bases using the MiSeq platform. Sequenced data will then be analyzed using QIIME. The investigators hypothesize that participants receiving the DASH diet will have a greater increase in alpha diversity and greater changes in abundances of CRC-associated microbes than participants receiving the standard American diet. The investigators will also evaluate functional-level markers including bile acid and short chain fatty acid (SCFA) production and inflammatory markers. If the investigator's hypothesis is supported, they expect to see reduced production of secondary bile acids (e.g., deoxycholic acid), greater SCFA production (e.g, butyrate), and reduction in gut and systemic inflammation (e.g, calprotectin, IL-6) among participants receiving the DASH diet compared to the standard American diet. The investigator's findings will provide preliminary evidence for the DASH diet as an approach for cultivating a healthier gut microbiota across racially diverse populations. These findings can impact clinical, translational, and population-level approaches for modification of the gut microbiota to reduce risk of chronic diseases like CRC.

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2020-08-29
• Study First Submitted QC: 2020-08-29
• Study First Posted: 2020-09-04
• Study Start: 2022-03-07
• Status Verified: 2025-05
• Last Update Submitted: 2025-05-20
• Last Update Posted: 2025-05-21
• Primary Completion: 2026-05-31
• Study Completion: 2026-05-31

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 112

Inclusion Criteria

• black or white race
• non-Hispanic ethnicity
• age 19-65 years
• able to travel to the UAB Bionutrition Unit daily to retrieve meals

Exclusion Criteria

• gastrointestinal (GI) conditions i.e., irritable bowel, diverticulitis, peptic ulcers, Crohn's, GI cancers, and adenatomous polyps
• antibiotic or probiotic use in the previous 90 days
• smoking/tobacco use
• heavy alcohol consumption
• major medical conditions (e.g., renal disease, diabetes, cancer

Study & Design

• Study Type: INTERVENTIONAL
• Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
standard American diet	standard American diet	calorie-restricted standard American diet (35% fat; 51% carbohydrate; %15 protein; 14 g fiber)
DASH Diet	DASH Diet	calorie-restricted DASH diet (25% fat; 57% carbohydrate; 18% protein; 34 g fiber)

Primary Outcome Measures

Name	Time	Method
Diet-specific changes in inflammatory marker	day 28 - day 42	The investigators will calculate changes in interleukin-6 in pg/L
Diet specific changes in secondary bile acids	day 28 - day 42	The investigators will calculate changes in cholic acid in milligrams
Mean change in alpha diversity	day 28 - day 42	The investigators will assess the difference in alpha diversity determined by analyzing fecal samples.

Trial Locations

Locations (1)

Moffitt Cancer Center; 🇺🇸 Tampa, Florida, United States