Walnut Consumption and Gut Microbiota

NCT05441748 | Unknown

• 1 other identifier: 20164
• Study Type: interventional
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

Obesity is a growing health issue that effects the majority of adults in the United States. Prevalence of other metabolic diseases are increased in obese adults, including systemic inflammation. There is emerging evidence that the gut microbiota have a mediating role in controlling inflammation by producing butyrate when ingested fiber is fermented. Since these microbes are modifiable by diet, the investigators plan to introduce walnuts to the diets of participants with obesity because they are rich in fiber and unsaturated fatty acids. The purpose of this study is to understand the impacts of walnut consumption on the gut microbiota and the effect they have on bile acid profiles and systemic inflammation. The investigators intention is to identify how these walnut-derived molecules influence Faecalibacterium spp., a butyrate producing microbe. Increased levels of butyrate have shown to decrease secondary bile acids and decrease inflammation.

Conditions

Obesity; Inflammation

Keywords

Walnuts; gastrointestinal microbiota; bile acid profiles; inflammation; glycemia; insulinemia

Outcome Measures

Primary Outcomes (2)

• Fecal Microbial Species

  Abundances of fecal Faecalibacterium spp. and Roseburia spp measured using metagenomic sequencing in walnut and walnut oil vs. control.

  Fecal samples will be collected at the end of each 3 week condition.

• Concentration of fecal bile acids

  Fecal bile acid concentrations measured using HPLC in walnut and walnut oil vs. control

  Fecal samples will be collected at the end of each 3 week condition.

Secondary Outcomes (1)

• Fecal Microbial Metabolites

  Fecal samples will be collected once at the end of each 3 week condition.

Other Outcomes (5)

• Fecal Microbiome

  Fecal samples will be collected at the end of each 3 week condition.

• Inflammatory markers

  Blood samples will be collected at the end of each 3 week condition.

• Serum bile acid profiles

  Blood samples will be collected during a mixed-meal tolerance test that occurs at the end of each 3 week condition.

Study Arms (3)

Intervention treatment

EXPERIMENTAL

Intervention treatment will contain walnuts and be consumed everyday for 3 weeks.

Other: Walnuts

Intervention treatment oil

EXPERIMENTAL

Intervention treatment will contain walnut oil in foods and be consumed everyday for 3 weeks.

Other: Walnut Oil

Control treatment

PLACEBO COMPARATOR

Intervention treatment will contain corn oil in foods and be consumed everyday for 3 weeks.

Other: Control

Interventions

Walnuts OTHER

The intervention treatment will contain walnuts.

Intervention treatment

Walnut Oil OTHER

The intervention treatment will contain walnut oil.

Intervention treatment oil

Control OTHER

The control treatment will contain corn oil.

Control treatment

Eligibility Criteria

• Age: 25 Years - 75 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Participants will include adults ages 25-75 years BMI of \> 30 kg/m2 Ability to drop-off fecal sample within 15 minutes of defecation

You may not qualify if:

• Walnut allergy or intolerance
• Food allergies or intolerances
• Prior diagnosis of metabolic or gastrointestinal disease (cardiovascular disease and type 1 or type 2 diabetes, chronic constipation, diarrhea, Crohn's disease, celiac disease, ulcerative colitis, irritable bowel syndrome, diverticulosis, stomach or duodenal ulcers, hepatitis, HIV, cancer, etc.)
• Women that are pregnant, had a baby within the last 12 months, or lactating
• Individuals that smoke, use tobacco, abuse drugs, or consume \> 2 alcoholic beverages per day.
• \> 5% weight change in the past month or \> 10% change in the past year
• Oral antibiotics during the previous 6 weeks
• Fasting blood glucose \>126 mg/dL, blood pressure \>160/100 mm Hg, elevation in serum transaminases (i.e. \>3 times the upper limit of normal) or with evidence of liver disease, including primary biliary cirrhosis or gallbladder disease, constipation, are currently taking lipid-lowering medications, oral hypoglycemic agents, or insulin, or certain medications (laxatives, bile acid sequestrants, and opiates)
• History of malabsorptive or restrictive bariatric surgeries (e.g., gastric bypass, sleeve gastrectomy, adjustable gastric band) or gall bladder removal surgery.
• Are unable to consume the experimental meals/snacks.
• Participants who have donated blood within the last 8 weeks
• Recent diagnosis of anemia
• Concurrent enrollment in another dietary, exercise, or medication study

Sponsors & Collaborators

• University of Illinois at Urbana-Champaign: lead

Study Sites (1)

Hannah Holscher

Urbana, Illinois, 61801, United States

Location

MeSH Terms

Conditions

Obesity; Inflammation

Condition Hierarchy (Ancestors)

Overweight; Overnutrition; Nutrition Disorders; Nutritional and Metabolic Diseases; Body Weight; Signs and Symptoms; Pathological Conditions, Signs and Symptoms; Pathologic Processes

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: SINGLE
• Who Masked: PARTICIPANT
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Associate Professor

Study Record Dates

• First Submitted: May 6, 2021
• First Posted: July 1, 2022
• Study Start: June 1, 2022
• Primary Completion: August 1, 2023
• Study Completion: July 1, 2024
• Last Updated: June 18, 2023

Record last verified: 2023-06

Locations

US (1)