The kidneys play a key role in maintaining fluid and electrolyte homeostasis, excretion of metabolic waste products, and regulation of various hormonal and metabolic pathways. Even a slight reduction in renal function may therefore have metabolic and nutritional consequences. Patients with chronic kidney disease (CKD) display a variety of metabolic and nutritional abnormalities and a large proportion of the patients demonstrate signs of protein-energy wasting (PEW) [1, 2], and these problems become more severe when patients reach the stage of end-stage renal disease (ESRD) [2, 3], a condition that, by definition, means the need to start life-saving renal replacement therapy by dialysis or kidney transplantation.