An interventional study of Inulin and Maltodextrin (Placebo) in Obesity & Overweight, Perimenopausal Women and Prebiotics, sponsored by George Washington University. Recruiting at 1 site in United States. Open to female participants aged 40 Years to 55 Years. Per ClinicalTrials.gov, last updated 2026-08-11.
Sponsored by George Washington University · Not applicable, Interventional, and Prevention
This study aims to evaluate the effects of 2 weeks of inulin supplementation in perimenopausal women with overweight or obesity. The primary questions this study seeks to answer are:
Researchers will compare inulin with a placebo (a similar-looking supplement that does not contain inulin) to determine whether inulin influences gut and vaginal microbial function, cardiovascular health, and skeletal muscle health during the perimenopausal transition.
Participants will:
This proposal presents a proof-of-concept study of the Prebiotic Inulin for Late Reproductive Individuals (PILI) intervention, a prebiotic fiber supplementation among women with perimenopause and overweight or obesity.
More specifically, the PILI intervention integrates multi-omics, physiological, and cardiometabolic assessments to examine the effects of inulin supplementation on overall health during the menopausal transition. Outcomes include changes in the gut and vaginal microbiome and their functional activity, gut-derived metabolites, vascular health, metabolic flexibility, skeletal muscle oxidative capacity, body composition, physical activity, sleep, dietary intake, and other cardiometabolic health markers. The target age range for this intervention is 40-55 years, reflecting the perimenopausal stage of life. Participants must also have overweight or obesity.
Participants will be randomly assigned to receive both the study intervention, inulin, and placebo, in a blind crossover design. Each participant will complete two intervention periods, separated by a washout period, allowing every participant to serve as her own control. Throughout the study, participants will consume the assigned supplement daily and attend scheduled in-person research visits before and after each intervention period.
At these visits, the research team will collect biological samples, including blood, stool, and vaginal swabs, and perform a comprehensive series of clinical assessments. These assessments include body composition, vascular health, metabolic flexibility, skeletal muscle oxidative capacity using near-infrared spectroscopy, physical function, and cardiometabolic testing. Participants will also complete questionnaires related to dietary intake, physical activity, sleep, menopausal symptoms, and quality of life, while wearing a Fitbit device to objectively monitor physical activity and sleep throughout the study.
The PILI study team will evaluate the feasibility of the intervention by assessing recruitment, retention, adherence to supplement consumption and study procedures, participant acceptability and tolerability, and completion of biological sample collection and clinical assessments. Preliminary changes in microbiome composition and function, microbial metabolites, and cardiometabolic health outcomes will also be evaluated to generate data that will inform the design of a future larger clinical trial.
This research has the potential to advance understanding of how prebiotic supplementation influences the gut-muscle-metabolism axis during the menopausal transition and to identify a safe, low-cost nutritional strategy to improve cardiometabolic health among perimenopausal women.
Exclusion Criteria:
Participants receive inulin daily for 2 weeks, followed by a 2-4 week washout period, then placebo for 2 weeks.
Dietary Supplement: Inulin · Dietary Supplement: Maltodextrin (Placebo)
Participants receive a placebo daily for 2 weeks, followed by a 2-4-week washout period, then inulin for 2 weeks.
Dietary Supplement: Inulin · Dietary Supplement: Maltodextrin (Placebo)
10g per day for 2 weeks
10g per day for 2 weeks
Change in Gut Microbiome Composition
Change in gut microbiome composition, assessed by shotgun metagenomic sequencing, comparing inulin versus placebo in a randomized crossover design.
Time frame: Baseline, end of each 2-week intervention period (inulin and placebo), and after washout period (2-4 weeks).
Change in Gut Microbiome Functional Capacity
Change in gut microbiome functional capacity, including biosynthetic gene clusters (BGCs) and estrobolome-related microbial pathways, assessed by shotgun metagenomic sequencing, comparing inulin versus placebo in a randomized crossover design.
Time frame: Baseline, end of each 2-week intervention period (inulin and placebo), and after washout period (2-4 weeks).
Change in Vaginal Microbiome Composition
Change in vaginal microbiome composition, assessed by shotgun metagenomic sequencing, comparing inulin versus placebo in a randomized crossover design.
Time frame: Baseline, end of each 2-week intervention period (inulin and placebo), and after washout period (2-4 weeks).
Vascular Function
Change in vascular function, assessed by pulse-wave velocity (PWV), comparing inulin versus placebo in a randomized crossover design.
Time frame: Baseline and end of each 2-week intervention period (inulin and placebo), with assessments conducted during each intervention period following the washout phase (2-4 weeks).
Metabolic Flexibility
Change in metabolic flexibility, assessed as the change in respiratory exchange ratio (RER) from the fasted resting state to the postprandial period following a standardized high-fat mixed meal, measured continuously via indirect calorimetry, comparing inulin versus placebo in a randomized crossover design.
Time frame: Baseline and end of each 2-week intervention period (inulin and placebo), with assessments conducted during each intervention period following the washout phase (2-4 weeks).
Skeletal muscle mitochondrial oxidative capacity
Change in skeletal muscle mitochondrial oxidative capacity in the gastrocnemius muscle, comparing inulin versus placebo in a randomized crossover design. Muscle oxidative capacity will be assessed using near-infrared spectroscopy (NIRS).
Time frame: Baseline and end of each 2-week intervention period (inulin and placebo), with assessments conducted during each intervention period following the washout phase (2-4 weeks)
Plan to share: No — Individual participant data (IPD) will not be shared because the dataset contains sensitive health and behavioral information, and full de-identification and public release are not planned within the scope of this study.
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