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

Recruitment & Eligibility

Status: Recruiting

Sex: All

Target Recruitment: 24

Inclusion 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

Exclusion Criteria

Not provided

Study & Design

Study Type: Interventional

Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Quantification of SCFAs in fecal samples;Quantification of whole-body lean mass with DXA;Quantification of hand grip strength;Chair stand test

Secondary Outcome Measures

Name	Time	Method
Quantification of thigh muscle composition with computed tomography;6-minute walk test;Quantification of gut bacterial metabolites in plasma;Quantification of gut bacterial composition in fecal samples;Quantification of pH in fecal samples