Impact of Diet on the Gut-Muscle Axis in Older Adults

NCT05549622 | Completed

• 1 other identifier: GRANT13386865
• Study Type: interventional
• Target: 31
• Locations: 1 country
• Sites: 1

Brief Summary

Muscle health declines during aging. One factor that may impact muscle health is the community of bacteria that live in our intestines, but studies aimed at improving muscle health by targeting the gut in older adults are sparse. The primary goal of this study is to use a diet that is enriched in soluble fiber, which is exclusively utilized by gut bacteria to make substances that can impact muscle health, to improve muscle-related measures in older adults.

Conditions

Sarcopenia; Dietary Exposure; Microbial Colonization

Keywords

skeletal muscle; soluble fiber; gut-muscle axis; microbiome; SCFA; Uremic metabolites

Outcome Measures

Primary Outcomes (4)

• Quantification of SCFAs in fecal samples

  Fecal levels of bacterial metabolites, including acetate, propionate, and butyrate will be determined at the baseline and week-13 study visits

  Change from baseline when compared with the Week-13 visit

• Quantification of whole-body lean mass with DXA

  Measurement of whole-body lean mass will be determined at the baseline and week-13 study visits

  Change from baseline when compared with the Week-13 visit

• Quantification of hand grip strength

  Grip strength will be determined at the baseline and week-13 study visits

  Change from baseline when compared with the Week-13 visit

• Chair stand test

  The number of chair stands that can be performed in 30 seconds will be determined at the baseline and week-13 study visits

  Change from baseline when compared with the Week-13 visit

Secondary Outcomes (5)

• Quantification of thigh muscle composition with computed tomography

  Change from baseline when compared with the Week-13 visit

• 6-minute walk test

  Change from baseline when compared with the Week-13 visit

• Quantification of gut bacterial metabolites in plasma

  Change from baseline when compared with the Week-13 visit

• Quantification of gut bacterial composition in fecal samples

  Change from baseline when compared with the Week-13 visit

• Quantification of pH in fecal samples

  Change from baseline when compared with the Week-13 visit

Study Arms (2)

Low-soluble fiber diet

OTHER

Other: Low-soluble fiber diet

High-soluble fiber diet

ACTIVE COMPARATOR

Other: High-soluble fiber diet

Interventions

Low-soluble fiber diet OTHER

12 older adults (\>65y) will be randomized to consume the USDA Guidelines for fiber intake (10g of total fiber/1000 calories), as the low-soluble fiber diet

Low-soluble fiber diet

High-soluble fiber diet OTHER

12 older adults (\>65y) will be randomized to consume 34-35g of total fiber/1000 calories, as the high-soluble fiber diet

High-soluble fiber diet

Eligibility Criteria

• Age: 65 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Older Adult (65+)

You may qualify if:

• Independently living older adults (\> 65y)
• Sedentary (Godin-Shepard Leisure Time Physical Activity Questionnaire score \< 10)
• Non-smoking
• Not already consuming a high-fiber diet (\> 22, 28 g/day for women, men)
• Free of gastrointestinal disease (gastrointestinal cancer, inflammatory bowel disease, bariatric surgery, irritable bowel syndrome)
• Fluent in English
• Willing to attend three study visits (enrollment, baseline, and week-13)
• Willing to consume an abundance of fruits, vegetables, nuts/seeds
• Willing to consume an abundance of soluble fiber-rich foods (broccoli, brussels sprouts, flaxseeds sweetened with dates, lima beans, butternut squash, carrots, collard greens)
• Willing to tolerate mild gastrointestinal discomfort (bloating, belly grumbling, flatulence). Note that all attempts will be made to replace foods that may trigger these issues.
• Willing to not consume antibiotics during the 13-week study
• Willing to not schedule a colonoscopy during the 13-week study

You may not qualify if:

• Unwilling to visit the Tufts Human Nutrition Research Center on Aging (HNRCA) 3x/week to pick up the pre-prepared study diet
• Unwilling to only consume the provided food (unsweetened tea and/or black coffee are allowed)
• Food allergies related to foods that are included in the study
• Chewing problems
• Unwilling to wear a daily step counter (pedometer)
• Unwilling to complete a daily questionnaire that will assess gastrointestinal comfort
• Malnutrition (BMI \< 18.5 kg/m2)
• Use of supplemental probiotics or antibiotics, participation in an investigational drug evaluation, or a recent change in habitual medication use within the 1 month-period prior to the screening visit
• \> 5% weight loss or weight gain within the past 6-months
• A recent history of alcohol abuse (within the past 5 years)
• A history of any significant injury or surgery that currently affects physical functioning and ability to perform physical function testing
• Treatment with immunosuppressive drugs
• A prior diagnosis of organ failure (heart, liver, renal, respiratory)
• Diabetes mellitus (type 1, or type 2 with insulin therapy)
• Chronic kidney disease (eGFR ≤ 30 mL/min/1.73 m2)

Sponsors & Collaborators

• Tufts University: lead

Study Sites (1)

Jean Mayer Human Nutrition Research Center on Aging at Tufts University

Boston, Massachusetts, 02111, United States

Location

MeSH Terms

Conditions

Sarcopenia; Communicable Diseases

Condition Hierarchy (Ancestors)

Muscular Atrophy; Neuromuscular Manifestations; Neurologic Manifestations; Nervous System Diseases; Atrophy; Pathological Conditions, Anatomical; Pathological Conditions, Signs and Symptoms; Signs and Symptoms; Infections; Disease Attributes; Pathologic Processes

Study Officials

• Michael S Lustgarten, PhD

  Scientist II, NEPS Laboratory

  STUDY DIRECTOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: QUADRUPLE
• Who Masked: PARTICIPANT, CARE PROVIDER, INVESTIGATOR, OUTCOMES ASSESSOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Principal Investigator

Model Details: 24 older adults (\> 65y) will be randomized to consume a high- or low-soluble fiber diet

Study Record Dates

• First Submitted: August 24, 2022
• First Posted: September 22, 2022
• Study Start: March 1, 2023
• Primary Completion: April 30, 2025
• Study Completion: April 30, 2025
• Last Updated: July 18, 2025

Record last verified: 2024-08

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)