Prebiotics, Gut Microbiota, and Cardiometabolic Health

Inclusion Criteria: * Men and women; postmenopausal women not taking hormone replacement therapy. * Fasting glucose between 5.6 - 6.9 mmol/L and/or a 2h plasma glucose between 7.8-11.1 mmol/L following a 75 g oral glucose tolerance test. * Weight stable for previous 6 months (+/- 2.0 kg). * Sedentary to recreationally active * Willing to be randomized to treatment or placebo. * Verbal and written informed consent. * No plans to gain/lose weight or change physical activity level. * Willing to pick up food daily, and consume foods provided for the 6-week controlled feeding period. Exclusion Criteria: * BMI less than 25 kg/m2 or greater than 40 kg/m2 or body mass greater than 300 pounds due to limit of DEXA. * Diabetes or diabetes medications * Prebiotic or probiotic supplement or product consumption in prior 3 months. * Total cholesterol \> 6.2 mmol/L; triglycerides \> 4.5 mmol/L. * Blood pressure \> 140/90 mmHg or antihypertensive medications. * Diagnosed inflammatory disease (e.g. lupus, irritable bowel, periodontal disease, etc) * Fructo, galacto-, xylo-oligosaccharide intake \> 3 g/day. * Past or current ischemic heart disease, stroke, respiratory disease, endocrine or metabolic disease, neurological disease, or hematological-oncological disease. * Smoking, alcohol consumption \> 2 servings /d for males and 1 serving/d for females, or taking medications (including but not limited to statins or other drugs with anti-inflammatory actions) or antioxidant vitamins or supplem…