This study will assess whether dietary fiber supplements can reduce the production of chemicals which are produced by colon bacteria and normally excreted from the body by the kidney, but build up in the body in patients on hemodialysis.

The study procedures will consist of:

• taking a dietary supplement containing either fiber or starch (starch serves as a control for fiber) for six weeks. The fiber dose initially employed will be 30 g/day of high amylose corn and the control starch dose employed will be 30 g/day of waxy corn starch. Supplements which come in dry powder form will be mixed in liquid or food for consumption.
• filling out a food record and a quality of life questionnaire
• keeping a diary of any gi symptoms
• collecting samples of blood, spent dialysate, urine(if the patient still makes urine) and stool.

Inclusion Criteria:

• stable dialysis patients able to provide consent.

Exclusion Criteria:-- known g.i. disease

• use of antibiotics for the last two month or expected antibiotic use
• recent hospitalization or other event resulting in instability of food intake