Clinical trials
Dietary Fiber clinical trials
Below are recruiting dietary fiber clinical trials, each written for real people, not researchers. We’re tracking 20 recruiting studies, each written for real people, not researchers, below.
Recruiting studies
- NCT04611217Recruiting
Testing fiber to change gut bacteria and help with fullness
This study tests how eating different amounts of dietary fiber affects your gut bacteria and how full you feel. You may be able to help researchers understand whether fiber can support appetite and metabolic health.
Columbia, MissouriAges 20–55 - NCT07594600Recruiting
Fiber Diet Effects on Breath Compounds in Healthy Adults
This study examines how different amounts of dietary fiber affect natural chemical compounds released in your breath. Researchers will measure these compounds to understand how fiber influences your gut health and digestion.
ÖrebroAges 18–65 - NCT05643859Recruiting
Fiber supplement study for bowel health and gut bacteria
This study tests whether adding a dietary fiber supplement can change the bacteria in your colon (gut microbiome). You may be asked to take the fiber supplement during evaluation for a non-cancer rectal condition.
Portland, OregonAges 18 years+ - NCT06212817Recruiting
Dietary fiber before colorectal cancer surgery
This study tests whether eating extra dietary fiber before colon cancer surgery helps recovery. You'll receive fiber-rich foods or a placebo for 2-3 weeks before your operation.
Arnhem, GelderlandAges 18 years+ - NCT04829136Recruiting
Oral fiber supplement during donor stem cell transplant
This trial tests whether taking a fiber supplement by mouth during a donor stem cell transplant helps patients tolerate treatment and potentially recover better. It’s specifically for adults who are planning a donor (allogeneic) transplant for blood cancers.
Seattle, WashingtonAges 18 years+ - NCT06955975Recruiting
Pectin supplement for frailty in older adults
This study tests if daily pectin, a fiber found in fruits, can improve strength and health in older adults who are frail or pre-frail. It compares pectin to a placebo over time.
Nottingham, NottinghamAges 65 years+ - NCT06634186Enrolling by invitation
Fiber-rich diet for liver cirrhosis patients
This study tests whether eating more dietary fiber can improve outcomes for people with liver cirrhosis and high blood pressure in the liver (portal hypertension). If you have cirrhosis, adding fiber to your diet might help.
Hanover, Lower SaxonyAges 18 years+ - NCT07724522Recruiting
Prebiotic Fiber for Irregular Periods in Women
This study tests whether taking a prebiotic fiber (inulin) can help women who are in the later years of their reproductive life (before menopause) and have irregular periods. You may be eligible if you are overweight, have irregular cycles, sit a lot, and do not exercise much.
Washington D.C., District of ColumbiaAges 40–55 - NCT05067595RecruitingPhase 1
Fecal transplant plus fiber for gut graft-versus-host disease
This Phase 1 study tests whether a fecal microbiota transplant (a stool-based treatment from a screened donor) plus a dietary fiber supplement can improve gut symptoms after a bone marrow transplant. It is aimed at people with mild to severe gut graft-versus-host disease (GVHD).
Seattle, WashingtonAges 18 years+ - NCT07686835RecruitingPhase 2
High-fiber diet to help immunotherapy work better in advanced melanoma
This trial tests if adding extra dietary fiber before and during immunotherapy can change gut bacteria to make the treatment more effective. It is for people with advanced melanoma who are about to start their first immunotherapy.
Nijmegen, GelderlandAges 18 years+ - NCT06424522Recruiting
Enema program for bowel problems after rectal cancer surgery
This trial tests a special enema program to help people with ongoing bowel problems (called LARS) after rectal cancer surgery. If standard treatments haven't worked, this program might offer a new way to manage symptoms like urgency and leakage.
Columbus, OhioAges 18 years+ - NCT07683936RecruitingEarly Phase 1
Fecal transplant for brain issues after liver procedure
This trial tests if transferring healthy bacteria into your gut (fecal microbiota transplant) can help people who still get confusion episodes (hepatic encephalopathy) even after a TIPS procedure and while on standard medications like lactulose and rifaximin.
Xi'anAges 18–75 - NCT07007169RecruitingPhase 2
Mediterranean diet study for early breast cancer
This trial tests whether eating a Mediterranean-style diet (rich in vegetables, fruits, whole grains, and healthy fats) can help improve outcomes for women with early breast cancer who are receiving chemotherapy. You will be asked to follow this diet and keep a food diary using an online tool.
EsbjergAges 18 years+ - NCT07218640Recruiting
Stool sampling study with chia seeds for adults
This trial asks adults to eat chia seeds and provide stool samples several times a week. Researchers want to learn more about digestion and gut health by studying the samples.
Ambler, PennsylvaniaAges 18–50 - NCT07622914Recruiting
Dietary fiber and muscle health in head and neck cancer
This study tests whether eating more fiber can help prevent muscle loss in people newly diagnosed with head and neck cancer. Researchers will track your nutrition and muscle strength over time to see if dietary fiber makes a difference.
Oklahoma City, OklahomaAges 18 years+ - NCT07447505Recruiting
High-protein, high-fiber pre-fast meal study
This trial tests if eating a high-protein, high-fiber meal before fasting helps you feel full longer and keeps your blood sugar stable. It may help people who fast and want to avoid hunger or sugar dips.
Al-Ahsa, Eastern ProvinceAges 18 years+ - NCT07590804Recruiting
Plant-Based Diet Study for Blood Cell Cloning
This study tests whether eating more plant-based whole foods can help people with clonal hematopoiesis (a condition where blood cells grow from a single mutated cell). Researchers want to understand if dietary changes affect this condition and collect health information over time.
Basking Ridge, New JerseyAges 18 years+ - NCT05805319Recruiting
Food intervention for people with lung cancer on immunotherapy
This trial studies whether a specific diet can help people with non-small cell lung cancer who are receiving immunotherapy (a standard cancer treatment). It mainly checks whether participants can follow the diet plan and tolerate the food changes safely.
Montreal, QuebecAges 18 years+ - NCT06475807Recruiting
Dietary changes for people on immunotherapy for cancer
This study tests whether a change in diet can help people with early-stage melanoma or lung cancer who are receiving immunotherapy (a type of treatment that helps your immune system fight cancer). You will be asked to follow a diet, give blood and stool samples, and complete questionnaires to see how the diet affects your body and treatment.
Pittsburgh, PennsylvaniaAges 18 years+ - NCT07501377Recruiting
Diet and brain health study for women in menopause with overweight
This trial tests whether a diet rich in fiber and plant compounds (polyphenols) can reduce brain inflammation in perimenopausal women who are overweight. If you're in early menopause and have some inflammation, this study may show how diet affects your brain health.
Leipzig, SaxonyAges 35–60
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Common questions
- Are there clinical trials for dietary fiber?
- Yes. Clin2 currently lists 20 recruiting dietary fiber studies from the U.S. registry, each rewritten for real people, not researchers, so you can see what it’s testing and who it’s for.
- How do I know if I qualify for a dietary fiber trial?
- Each study lists its eligibility criteria — rules about age, diagnosis, and prior treatments. On every Clin2 trial page we explain these in words written for real people and offer a short, optional pre-screen for a fit read. The study team makes the final decision.
- Does it cost anything to join a dietary fiber trial?
- Using Clin2 is always free. Many trials cover the cost of the study treatment and related visits; some reimburse travel. The study team explains exactly what’s covered before you decide.
Related conditions
Clin2 helps you find and understand clinical trials and does not provide medical advice. Study data comes from ClinicalTrials.gov. Talk with your doctor about whether a specific trial is right for you.