Effects of diet on muscle health in older adults

Impact of a High-Soluble Fiber Diet on the Gut-Muscle Axis in Older Adults

This study tests if a diet high in soluble fiber can help improve muscle health and quality of life for older adults.

Quick facts

• Phase: Not applicable
• Study type: Interventional
• Enrollment: 24 (estimated)
• Ages: 65 Years and up
• Sex: All
• Sponsor: Tufts University (Academic / other)
• Locations: 1 site (Boston, Massachusetts)
• Trial ID: NCT05549622 on ClinicalTrials.gov

What this trial studies

This study investigates how a diet enriched in soluble fiber can influence muscle health in older adults by targeting the gut-muscle axis. It aims to understand the relationship between gut bacteria, their metabolites, and muscle composition and function. Participants will be assigned to either a low-soluble fiber diet or a high-soluble fiber diet over a 13-week period, with assessments conducted at enrollment, baseline, and week 13. The study seeks to elucidate mechanisms that could improve muscle-related measures and overall quality of life in the aging population.

Who should consider this trial

Good fit: Ideal candidates are independently living older adults over 65 years who are sedentary and not consuming a high-fiber diet.

Not a fit: Patients with gastrointestinal diseases or those already on a high-fiber diet may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could lead to dietary interventions that enhance muscle health and reduce frailty in older adults.

How similar studies have performed: While studies on the gut-muscle axis are limited, there is emerging evidence suggesting that dietary interventions targeting gut health can positively impact muscle health.

Eligibility criteria

Inclusion Criteria:

1. Independently living older adults (\> 65y)
2. Sedentary (Godin-Shepard Leisure Time Physical Activity Questionnaire score \< 10)
3. Non-smoking
4. Not already consuming a high-fiber diet (\> 22, 28 g/day for women, men)
5. Free of gastrointestinal disease (gastrointestinal cancer, inflammatory bowel disease, bariatric surgery, irritable bowel syndrome)
6. Fluent in English
7. Willing to attend three study visits (enrollment, baseline, and week-13)
8. Willing to consume an abundance of fruits, vegetables, nuts/seeds
9. Willing to consume an abundance of soluble fiber-rich foods (broccoli, brussels sprouts, flaxseeds sweetened with dates, lima beans, butternut squash, carrots, collard greens)
10. 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.
11. Willing to not consume antibiotics during the 13-week study
12. Willing to not schedule a colonoscopy during the 13-week study

Exclusion Criteria:

1. Unwilling to visit the Tufts Human Nutrition Research Center on Aging (HNRCA) 3x/week to pick up the pre-prepared study diet
2. Unwilling to only consume the provided food (unsweetened tea and/or black coffee are allowed)
3. Food allergies related to foods that are included in the study
4. Chewing problems
5. Unwilling to wear a daily step counter (pedometer)
6. Unwilling to complete a daily questionnaire that will assess gastrointestinal comfort
7. Malnutrition (BMI \< 18.5 kg/m2)
8. 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
9. \> 5% weight loss or weight gain within the past 6-months
10. A recent history of alcohol abuse (within the past 5 years)
11. A history of any significant injury or surgery that currently affects physical functioning and ability to perform physical function testing
12. Treatment with immunosuppressive drugs
13. A prior diagnosis of organ failure (heart, liver, renal, respiratory)
14. Diabetes mellitus (type 1, or type 2 with insulin therapy)
15. Chronic kidney disease (eGFR ≤ 30 mL/min/1.73 m2)
16. Overt disease (cancer, dementia, cardiovascular disease)
17. Chronic use of anti-inflammatory medication (corticosteroids)
18. Already enrolled in another research study
19. Active infection, including Tuberculosis , HIV, malaria, hepatitis, shingles, Methicillin-Resistant Staphylococcus Aureus (MRSA), SARS-CoV-2
20. Any major illness or condition that may interfere with study outcomes at the discretion of the study physician
21. Won't remain in Boston for the 13-week study duration
22. Unwilling to complete a daily checklist aimed at quantifying the amount of food eaten on the study diet

Where this trial is running

Boston, Massachusetts

• Jean Mayer Human Nutrition Research Center on Aging at Tufts University — Boston, Massachusetts, United States (Recruiting)

Study contacts

• Study coordinator: Michael S Lustgarten, PhD

Conditions Sarcopenia; Dietary Exposure; Microbial Colonization; skeletal muscle; soluble fiber; gut-muscle axis; microbiome; SCFA