The Food Environment, Microbial Cysteine Metabolism, and Cancer Disparities (NCT07086833)
🩺 Plain-English Summary (8th-Grade Level)
The goal of this clinical trial is to learn if changing cysteine levels in the diet can influence how the body processes cysteine in Black and White individuals aged 45-75 with a history of non-cancerous polyps. The main questions it aims to answer are: * At the beginning of the study, do Black participants have higher levels of cortisol (a stress hormone) and compounds made from cysteine in their blood when compared to White participants? * Does eating less cysteine lower the body's natural cysteine activity and lead to less gut bacteria that break down cysteine? * Does eating less cysteine lead to less inflammation in the gut and lower levels of markers of inflammation in the blood? Research will compare a high cysteine diet and a low cysteine diet, and each participant will eat both diets. Participants will be in the study for 11 weeks and 2 days. Over the course of the study, participants will: * Eat a high cysteine diet for 3 weeks, and a low cysteine diet for 3 weeks * Eat a moderate cysteine diet for 1 week before each study diet * Complete surveys * Provide blood, stool, and saliva samples * Maintain food logs
Who can join: To join this study, participants generally need to meet the listed inclusion criteria (6 items) and avoid the listed exclusions (18 items).
Location: University Hospital Clinical Research Center — Indianapolis, Indiana
📋 "Do I Qualify?" — 1-Minute Self Screener
Instant ChecklistCheck every box below. If you can check all of them, you may meet the study's basic screening requirements (final eligibility is confirmed by the site team).
Usually NOT eligible if any of the following apply:
- Exclusion Criteria:
- Antibiotic use within the last 6 months
- Abnormal gastrointestinal transit
- A history of organ transplantation
- Use of illicit drugs, combustible tobacco, or dietary supplements
- Pre- or probiotics within the last two months
- A history of cancer treatment within the past 12 months
- CRC or a genetic predisposition to CRC
- A baseline body weight \> 450 lbs
- Weight gain or loss \> 4 kg 3 months prior to study
- Significant food allergies, food preferences or therapeutic or vegetarian diets
- Menstrual cycle within the last 6 months
🔍 Extracted verbatim from the official NIH eligibility criteria. Always confirm with the study coordinator.
📍 All Participating Trial Locations (2 Sites)
- University Hospital Clinical Research Center — Indianapolis, Indiana
- Purdue Clinical Research Center — West Lafayette, Indiana
💰 Cost, Insurance & Patient Rights
- 100% Free Items: The investigational treatment and protocol-required procedures are supplied at zero cost by the sponsor.
- Routine Patient Care: Under federal law (ACA § 2709) and many state statutes, routine care costs are covered during participation.
- Voluntary Participation: You may withdraw at any time without affecting your standard medical care.