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Search / Trial NCT06395324

Fiber Effectively Educates & Directs the Microbiome Study

Launched by UNIVERSITY OF CALIFORNIA, DAVIS · Apr 29, 2024

Trial Information

Current as of June 26, 2025

Recruiting

Keywords

Fecal Microbiome Arabinose Fecal Glycome Fecal Short Chain Fatty Acids Fiber High Arabinose Diet

ClinConnect Summary

The FEEDMe Study is a research project looking at how certain foods that contain a type of sugar called arabinose can affect the bacteria in our gut, which is important for our overall health. This study is open to healthy adults aged 18 to 50 who live within 40 miles of UC Davis in California and eat meals or snacks at least three times a day. Participants should not drink alcohol excessively, have stable body weight, and should be willing to follow specific dietary guidelines for 18 days while providing stool samples and completing online surveys about their health and diet.

If you join this study, you’ll receive a variety of foods to eat and will need to track what you consume. You’ll also be asked to keep a daily record of your bowel movements and answer some questions about your health throughout the study. It’s important to note that there are certain restrictions on what you can eat and drink during this time, and you’ll need to avoid any medications or supplements that could change your gut bacteria. This study aims to better understand how our food choices can shape the community of microorganisms in our intestines, which may help improve health for everyone.

Gender

ALL

Eligibility criteria

  • Inclusion Criteria:
  • Healthy adults;
  • Age 18-50 years of age;
  • BMI between 18.5 and 34.9 kg/m2;
  • Lives within a 40-mile radius from the UC Davis campus in Davis or UCDMC in - Sacramento, CA or study personnel residences;
  • Consumes food at least three times (meals/snacks) per day;
  • Non-alcohol consumers or those who consume alcohol in moderation defined as having up to 1 drink per day for women and up to 2 drinks per day for men;
  • Normal stool frequency defined as 3 times per week to 3 times per day;
  • Has been weight-stable (has not lost or gained 10% of body weight) within the past 3 months;
  • Speaks, writes, and understands English to complete study activities;
  • Lives in a household whereby stool samples and study food can be reliably stored without interference from other household members (i.e., excluding individuals who reside in fraternity, sorority houses whereby freezer access is open to all members);
  • Lives in a household with access to Wi-Fi and/or cellular access to enable completion of electronic questionnaires (i.e., PIP forms) on their own personal computer, cell phone, or electronic device;
  • Willingness to consume study-provided foods for 18 consecutive days;
  • Willingness to fill out a short online survey about the amount of each study food they consumed during the two-week intervention;
  • Willingness to collect stool samples on three separate days and store them in their home freezer before they (or study personnel) transport them to UC Davis;
  • Willingness to complete online weekly health questionnaires;
  • Willingness to complete two online enrollment questionnaires about diet and health history;
  • Willingness to complete Daily Stool Logs (7 consecutive days) at 3 separate times during the study period;
  • Willingness to complete two 24-hour dietary recalls by video call with study personnel (prior to each of the 3 stool collections required for the study);
  • Willingness to have four in-person visits (at their homes or on campus);
  • Willingness to use their personal computer, cell phone, or electronic device to meet virtually with study personnel;
  • Willingness to refrain from consuming fermented foods, or foods with probiotics or probiotic supplements and other foods listed on the study materials (confounding variables of the intestinal microbiome) during the study period;
  • Willingness to refrain from consuming iron containing dietary supplements (multi-vitamin is permitted) and fiber supplements during the study period;
  • Willingness to refrain from changing (starting a new or discontinuing a current) routine vitamin/mineral supplement regimen during the study period;
  • Willingness to refrain from changing (starting a new or discontinuing a current) routine medication regimen during the study period;
  • Willingness to refrain from consuming laxatives during the study period;
  • Willingness to refrain from enrolling in other experimental trials during the study period;
  • Willingness to avoid binge alcohol drinking during the study period defined by the CDC as: drinking 5 or more drinks on a single occasion for men or 4 or more drinks on a single occasion for women, generally within about 2 hours;
  • Willingness to refrain from using tobacco (smoking or chewing or using E-cigarettes) or smoking, vaping or consuming cannabis or use of other illicit drugs during the study period;
  • Willingness to refrain from having any non-emergency, elective surgeries including dental surgery or invasive medical procedures during the study period;
  • Willingness to take a study-provided urine pregnancy test if female;
  • Mid- to high-income families and low-income families based on household income or eligibility for the California Supplemental Nutrition Assistance Program (SNAP) or Special Supplemental Nutrition Program for Women, Infants, and Children (WIC).
  • Exclusion Criteria:
  • Currently pregnant or plans to become pregnant several weeks prior to enrollment and during the study period;
  • Currently lactating;
  • Use of restrictive diets such as caloric restriction, intermittent fasting, keto-diet, gluten-free, grain-free, dairy-free within the past 6 months;
  • Known or suspected allergy (childhood allergies pre-puberty is acceptable) to milk, egg, wheat, legumes including soybeans; peanuts, tree nuts and seeds, and any fruits and vegetables used in the study;
  • Known or suspected sensitivity or intolerances to any foods and ingredients used in the study (e.g., lactose intolerance, etc.) such as milk, egg, wheat, legumes including soybeans, peanuts, tree nuts and seeds and any fruits and vegetables used in the study;
  • Aversions to or avoidance in eating foods and ingredients used in the study (legumes/beans, fruits, vegetables, peanuts, tree nuts and seeds);
  • History of any type of eating disorder (anorexia nervosa, bulimia, etc.);
  • History of any of the following: Positive infection of HIV, AIDS, hepatitis B or C; GI tract abnormalities; Any type of bariatric surgery or other gastric surgery involving the removal of sections of the GI tract (appendectomy or hernia repairs are acceptable), or gall-bladder removal; GI-related conditions such as malabsorption disease, celiac disease, Crohn's disease, colitis, inflammatory bowel disease (IBD), irritable bowel syndrome (IBS); Cancer (history of skin cancer that is in remission is acceptable), heart, liver, lung, endocrine, or kidney diseases; Type 1 or 2 diabetes mellitus; Cushing syndrome; Primary immune deficiency or autoimmune diseases; Uncontrolled hyper or hypothyroidism; uncontrolled hypertension (controlled with medication is acceptable);
  • History of stomach ulcers or diagnosis with H. pylori infection; chronic gastritis within the past 12 months;
  • Gastroenteritis (caused by stomach flu or food poisoning caused by virus or bacteria) within the past 4 weeks;
  • Have any medical or nutritional conditions that require iron supplementation;
  • Intake of iron supplements (stand-alone doses that are not part of a multi-vitamin) within the past 4 weeks;
  • Positive test for COVID-19 based on a rapid test or PCR within the past 2 weeks;
  • Use of oral, intramuscular or IV antibiotics or sulfonamides within the past 3 months;
  • Vaccinations received less than the past 2 weeks (may enroll two weeks following treatment with vaccinations);
  • Use of biologics that suppress the immune system, i.e., Lantus, Remicade, Rituxan, Humira, Herceptin, Avastin, Lucentis, Enbrel, for 2 weeks or longer or within the past 4 weeks;
  • Use of injectable (or pill) weight loss medications or biologics such as Ozempic, Wegovy, Rybelsus, etc. within the past 4 weeks;
  • Surgery or an invasive medical procedure within the past 3 months;
  • Plan to have any elective surgeries including dental surgery or invasive medical procedures during the study period;
  • Illness (flu, cold, etc.) within the past 2 weeks (free of all illness symptoms within the past 2 weeks);
  • Routine use of medications found to alter the gut microbiome such as: Tylenol, aspirin, naproxen sodium or ibuprofen (except for acute uses with sickness or injury), anticholinergic inhalers, opioids, proton pump inhibitors, gastric acid suppressors (e.g., pepcid), metformin, statins, steroids (oral-inhaler is acceptable), 6-Marcaptopurine, Azathioprine or any other immunosuppressants on a daily basis within the past 6 months;
  • Plans to start or plans to have changes made to a dose (including starting or adjusting an existing dose) of selective serotonin reuptake inhibitors (SSRIs), or antipsychotics during the study period;
  • Plans to start or plans to have changes made to a dietary supplement regimen (vitamins/minerals/herbal supplements) or a medication regimen during the study period;
  • Persistent (lasts longer than 2 weeks and less than 4 weeks) or chronic (lasts at least 4 weeks) diarrhea (loose, watery stools three or more times a day) within the past 6 months;
  • Chronic constipation (fewer than 3 stools per week, stool form that is mostly hard or lumpy and difficult stool passage (need to strain or incomplete evacuation) with the past 3 months;
  • Use of probiotic supplements within the past 8 weeks;
  • Individuals who use laxatives more than once per week;
  • Individuals who use fiber supplements more than once per week;
  • Current tobacco (smoking or chewing) or E-cigarette users or individuals who quit using less than one year before enrolling in the study;
  • Frequent cannabis use (eating, smoking, or vaping) defined as greater than 4 times per week and greater than 14 times per month;
  • Use of illicit drugs (cocaine, crack, heroine, unprescribed fentanyl etc.);
  • Excessive alcohol drinkers: For men, heavy drinking is typically defined as consuming 15 drinks or more per week. For women, heavy drinking is typically defined as consuming 8 drinks or more per week (https://www.cdc.gov/alcohol/faqs.htm);
  • Individuals who currently live or plan to live within the same household during the study period or who are in intimate relationships with current or past study participants (to avoid horizontal transfer of the gut microbiome),
  • Individuals who plan to travel during the stool collections and intervention phase of the study duration.

About University Of California, Davis

The University of California, Davis (UC Davis) is a leading research institution renowned for its commitment to advancing healthcare through innovative clinical trials and studies. With a strong focus on interdisciplinary collaboration, UC Davis leverages its extensive expertise in medical research, education, and patient care to drive breakthroughs in various fields, including medicine, public health, and agriculture. The university's clinical trial programs emphasize rigorous scientific methodology and ethical standards, aiming to translate research findings into impactful treatments and improved patient outcomes. Through its state-of-the-art facilities and a dedicated team of researchers and healthcare professionals, UC Davis is at the forefront of transforming healthcare practices and addressing critical health challenges.

Locations

Davis, California, United States

Patients applied

0 patients applied

Trial Officials

Jennifer Smilowitz, PhD

Principal Investigator

University of California, Davis

Timeline

First submit

Trial launched

Trial updated

Estimated completion

Not reported