Effects of Resistant Starch Diet on the Gut Microbiome in Chronic Kidney Disease

Inclusion Criteria: * Adult * Between the ages of 18 and 85 years old * Glomerular filtration rate estimated by creatinine clearance (eGFR Cr):between 59 and 30 ml/min for stage 3 CKD patients * Urine protein \< 1 gram per day by 24-hour protein collection or urine protein-to-creatinine ratio \<1 gram/gram or urine microalbumin to creatinine concentration less than 1000 mg/g. * Children * Between the ages of 5 and 17 years * eGFR Cr between 30 and 59 (stage 3 CKD) using the revised Schwartz equation. * Urine protein \< 1 gram per day by 24-hour protein collection or urine protein-to-creatinine ratio \<1 gram/gram. Exclusion Criteria: Adult * Age older than 85 years * eGFR Cr \> 59 ml/min or \< 30 ml/min * History of renal transplant * Subject with diabetes (as defined by patient report, taking medications for the treatment of diabetes or as reported in the medical record) * Use of antibiotics within 1 month * Use of laxatives within 1 month * Inflammatory bowel disease * Irritable bowel syndrome * Colorectal cancer * Surgically removed bowel or presence of an ostomy * Pregnancy * Inability to obtain written informed consent * Constipation * Diarrhea Children * Age younger than 5 years * eGFR \> 59 ml/min and \< 30 ml/min * History of renal transplant * Subject with diabetes (as defined by patient report, taking medications for the treatment of diabetes or as reported in the medical record) * Use of antibiotics within 1 month * Use of laxatives within 1 mon…