Modulation of the Gut Microbiome by Dietary Fiber to Improve Calcium Absorption and Bone Health in Older Men
VA Office of Research and Development
Summary
Osteoporotic fractures are a major but underrecognized problem in men. There is growing evidence that low dietary fiber intake is a modifiable risk factor for age-related bone loss in men. Preclinical and human studies in adolescents and postmenopausal women suggest that dietary fiber intake influences bone metabolism by modulating the gut microbiome to augment intestinal calcium absorption, but it is unclear through what molecular mechanism and whether dietary fiber has the same effects in older men. In this crossover intervention study, the investigators will enroll and follow 30 older male Veterans to evaluate the effects of soluble corn fiber on intestinal calcium absorption and explore the contribution of the gut microbiome.
Description
Osteoporosis and associated fractures are a major problem in older men. One in four men over the age of 60 will sustain an osteoporotic fracture during his lifetime. Moreover, the mortality rate in men after fractures is nearly twice that in women. Despite the burden of fractures, little is understood about the pathogenesis of progressive bone loss in men. Studies point to dietary fiber as a potentially important mitigator of decline in bone mass, likely through increased intestinal calcium absorption and retention, as studied in adolescents, young men, and postmenopausal women. However, the e…
Eligibility
- Age range
- 60+ years
- Sex
- Male
- Healthy volunteers
- Yes
Inclusion Criteria: * Male Veterans 60 years of age Exclusion Criteria: * History of malabsorption * Hypercalcemia (corrected Ca \> 10.2 mg/dL) * Vitamin D insufficiency (25OHD \< 30 ng/mL) * Chronic kidney disease stage 3B or worse (CrCl \< 45 mL/min) * Severe hypogonadism (AM fasting serum total testosterone \< 150 ng/dL) * Daily use of proton pump inhibitor * Use of medication(s) known to affect calcium metabolism * Use of medications or supplements that could impact gut microbiota in the previous 3 months (antibiotics or commercially available probiotics or prebiotics. * Presence of a c…
Interventions
- Dietary SupplementSoluble corn fiber
Soluble corn fiber, also referred to resistant maltodextrin, is a type of dietary fiber made from corn starch. Soluble corn fiber is typically used to thicken processed foods and has been marketed as a prebiotic to improve digestive health.
Location
- San Francisco VA Medical Center, San Francisco, CASan Francisco, California