Understanding how diet influences the gut microbiome and colorectal cancer risk

Is this trial a fit for you?

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This observational study aims to explore the relationship between dietary patterns and the microbiome in the digestive system, specifically focusing on individuals who are either strict vegetarians or omnivores. Researchers will evaluate differences in dietary habits, stool microbiome patterns, and somatic mutations in colorectal epithelial cells between these two groups. Participants will complete a dietary questionnaire and provide stool, blood, and tissue samples for detailed analysis. The goal is to identify potential associations between diet, microbiome composition, and colorectal cancer predisposition.

Why it matters

Who can join: the full rules

Inclusion Criteria:

* GROUP I: Patients presenting for a screening colonoscopy

  * GROUP I: Age of 45 and above
  * GROUP I: Strict vegetarian diet, determined by using diet history questionnaire 3.0 National Institutes of Health (NIH)
  * GROUP I: Non smoker
  * GROUP I: Ability to understand and willingness to sign an informed consent form, complete web based dietary assessment and provide stool, colonic mucosa and blood samples
  * GROUP II: Patients presenting for a screening colonoscopy
  * GROUP II: Age of 45 and above
  * GROUP II: Omnivorous diet
  * GROUP II: Non smoker
  * GROUP II: Ability to understand and willingness to sign an informed consent form, complete web based dietary assessment and provide stool, colonic mucosa and blood sample

Exclusion Criteria:

* • Current smokers (nicotine abuse only)

  * Positive family history of colon cancer or colon cancer related syndromes
  * Recent use of antibiotics in 1 month
  * History of inflammatory bowel disease, and/or radiation enteritis or colitis
  * Pregnant and breastfeeding women
  * Women of child-bearing potential who have positive urine or serum pregnancy test
  * Heavy drinker (defined as more than 14 drinks per week)
  * Currently using anti-flatulence medications, probiotics and/or fiber supplements
  * Major dietary restrictions and/or following a special diet
  * Patient with positive fecal test/symptoms

Where it's running

• M D Anderson Cancer Center
  Houston, Texas, United States Recruiting

Study contacts

• Principal investigator: Anusha Thomas, MD — MD Anderson Cancer Center, Houston, Texas
• Study coordinator: Anusha Thomas, MD
• Email: asthomas1@mdanderson.org
• Phone: 713-563-9600

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How to take part

1. Review the eligibility criteria above with your treating physician.
2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.