 Chronic kidney disease CKD patients have very low physical function and high rates of cardiovascular disease CVD mortality. The objective of the proposed research is to evaluate the effects of dietary supplementation with a pomegranate extract, that contains high amounts of antioxidants, on physical function and CVD risk. Patients with moderate to severe chronic kidney disease that are NOT yet on dialysis tend to have significantly reduced risk factors for cardiovascular disease and other disorders compared to dialysis patients. This includes significantly reduced systemic markers of oxidative stress and inflammation. As a result, therapies designed to reduce the risk of CKD co-morbidities may differ significantly in dialysis and pre-dialysis patients. For example, dialysis patients are recommended to INCREASE their intake of dietary protein, while pre-dialysis patients are recommended to DECREASE their protein intake, due to differences in the pathophysiology of the two conditions. The investigators have decided to recruit pre-dialysis patients in addition to dialysis patients in this study because the investigators believe this will help us determine if the efficacy of pomegranate differs between patients with different stages of CKD. 