Clinical trial NCT06935435: Effects of Distinct Nebraska-Dry Bean Market Classes on Gut Microbiota
Official title: Effects of Distinct Nebraska-Dry Bean Market Classes on Gut Microbiota
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Dietary Intervention
Gut Microbiota
Keywords: Dry Beans
Gut Microbiota
Nutritional Microbiology
Lead sponsor: University of Nebraska Lincoln
Sponsor class: OTHER
First posted: 2025-04-20
Enrollment: 12
Sex: ALL
Minimum age (years): 19
Maximum age (years): 50
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Intervention model description: The study intervention will consist of individuals consuming daily, precooked and prepackaged dry beans over three 2-week intervention periods. The amount of beans to consume will be ½ cups/day during week 1 and 1 ½ cups/day during week 2. The three bean interventions will be i) pink beans, ii) great northern beans, and iii) a five-bean mixture (pinto, kidney, black, pink, and great northern beans). The participants will be asked to consume all bean interventions in random order. The beans will be added to the participants' usual diet.
Primary purpose: OTHER

Brief summary: Beans are well known for their health benefits. Many of these benefits relate to gut health, as many of the nutrients found in beans support beneficial microbes that live in the gut. However, beans have a lot of genetic diversity. This diversity has led to different bean market classes with different colors, sizes, and nutrient profiles. Differences between bean market classes may trigger different effects on gut microbes and health, but this is poorly understood. The goal of the pilot clinical trial is to make comparisons (1) between two different bean market classes (pink beans, great northern beans) and (2) between a bean mixture (pinto, kidney, black, pink, and great northern beans) and individual bean market classes. The study will assess whether bean market classes differ in their effects on gut microbes, blood pressure, metabolism, and gut symptoms in adults with and without obesity.

Detailed description: Bean consumption delivers diverse dietary fibers (resistant starches, non-starch polysaccharides), proteins, polyphenols, and other compounds to the colon, where they serve as substrates for the microbial community (microbiota) that colonizes the gut of humans. However, dry beans exhibit high genetic diversity, corresponding with diverse pigments and nutrients across market classes. It remains poorly understood whether targeted effects on the gut microbiota and health measures are possible with distinct dry bean market classes. The overarching study objective is to perform a randomized, crossover pilot intervention trial in adults to determine the effects of consuming distinct dry bean market classes in isolation or combination on the gut microbiota and health. The study will compare the dose-dependent effects of pink beans, great northern beans, and a five-bean mixture (pinto, kidney, black, pink, and great northern beans) on the gut microbiota, health-relevant metabolites, blood pressure, and immunometabolic markers in adults with and without extra body weight. The pilot study will employ a 3-phase, cross-over design with 2-week intervention periods separated by 2-week washout periods.

Eligibility criteria: Inclusion Criteria:

1. Aged 19 to 50 years.
2. Not currently pregnant or planning to become pregnant (Females Only).
3. Stable body mass index (BMI) of either 18.5-24.9 kg/m2 or 27.0-39.9 kg/m2 for the last month.
4. Has not made any major dietary changes in the last month.
5. Able to read and speak English
6. Requires no legally authorized representative (LAR).
7. Not institutionalized (e.g., prison, psychological treatment center, etc.).
8. Able to wear ambulatory blood pressure monitor and limit physical activity over a 24-hr. period.
9. Have a bowel movement at least every other day.
10. Able to collect and deliver stool samples to Innovation Campus within 4 hours of collection.
11. No known allergies or intolerance to beans.
12. Able to avoid consuming beans during the study, except for the provided beans (up to 1.5 cups/day).

Exclusion Criteria:

1. Has a cardiac device.
2. History of organ transplant
3. History of gastrointestinal surgery or disease diagnosed by a physician that involves the stomach, small, and large intestines (e.g., IBD, IBS, chronic constipation, diverticulosis, gastric bypass).
4. Recent history of cancer (excluding skin cancer) in the last year.
5. Current use of tobacco or vaping.
6. Current or recent use (last 3 weeks) of digestive enzymes, laxatives, dietary fiber, prebiotic, or probiotic supplements.
7. Medication or supplement regimen or dosage changed within the last 2 months or 3 weeks, respectively.
8. Taken antibiotics in the last 2 months.
9. Known allergies or intolerances to beans.
10. BMI 18.5-24.9 kg/m2 (normoweight): Current use of oral or injectable medications for the treatment of most chronic conditions.
11. BMI 27.0-39.9 kg/m2 (overweight): Current use of oral or injectable medications for the treatment of diabetes, hypertension, cardiovascular, liver, kidney, gastrointestinal, or autoimmune.

Primary outcomes:
measure: 16S rRNA gene amplicon sequencing of the fecal bacterial community
timeFrame: From baseline to end of weeks 1 and 2 of treatment.
Secondary outcomes:
measure: Fecal short-chain fatty acids assessed by gas chromatography
timeFrame: From baseline to end of weeks 1 and 2 of treatment.
measure: Gastrointestinal symptoms assessed by the Gastrointestinal Symptom Rating Scale
timeFrame: From baseline to end of weeks 1 and 2 of treatment.
measure: Bowel movement habits assessed by a Bowel Habits Questionnaire
timeFrame: From baseline to end of weeks 1 and 2 of treatment.
Other outcomes:
measure: Blood pressure
timeFrame: From baseline to the end of treatment at 2 weeks.
measure: Systematic inflammation assessed by C-reactive protein
timeFrame: From baseline to the end of treatment at 2 weeks.
measure: Systematic inflammation assessed by glycosylated acute-phase proteins (GlycA)
timeFrame: From baseline to the end of treatment at 2 weeks.
measure: Glucose metabolism assessed by Homeostasis Model Assessment of Insulin Resistance (HOMA-IR)
timeFrame: From baseline to the end of treatment at 2 weeks.
measure: Glucose metabolism assessed by C-peptide
timeFrame: From baseline to the end of treatment at 2 weeks.
measure: Lipid metabolism assessed by a lipid panel
timeFrame: From baseline to the end of treatment at 2 weeks.
measure: Percent body fat assessed by bioelectrical impedance analysis
timeFrame: From baseline to the end of treatment at 2 weeks.
Locations:
city: Lincoln
country: United States
facility: Nebraska Food for Health Center
state: Nebraska
Study officials:
affiliation: University of Nebraska Lincoln
name: Edward C Deehan, PhD, RD
role: PRINCIPAL_INVESTIGATOR
References:
citation: Deehan EC, Yang C, Perez-Munoz ME, Nguyen NK, Cheng CC, Triador L, Zhang Z, Bakal JA, Walter J. Precision Microbiome Modulation with Discrete Dietary Fiber Structures Directs Short-Chain Fatty Acid Production. Cell Host Microbe. 2020 Mar 11;27(3):389-404.e6. doi: 10.1016/j.chom.2020.01.006. Epub 2020 Jan 30.
citation: Brewer GJ, Blue MNM, Hirsch KR, Saylor HE, Gould LM, Nelson AG, Smith-Ryan AE. Validation of InBody 770 bioelectrical impedance analysis compared to a four-compartment model criterion in young adults. Clin Physiol Funct Imaging. 2021 Jul;41(4):317-325. doi: 10.1111/cpf.12700. Epub 2021 Apr 1.
citation: Matthews DR, Hosker JP, Rudenski AS, Naylor BA, Treacher DF, Turner RC. Homeostasis model assessment: insulin resistance and beta-cell function from fasting plasma glucose and insulin concentrations in man. Diabetologia. 1985 Jul;28(7):412-9. doi: 10.1007/BF00280883.