Effect of diet on progression of chronic renal disease.

Changes in renal function induced by protein intake are thought to reflect evolutionary adaptation of the kidney. Excess dietary proteins over long periods may increase normal blood flow and glomerular filtration rate, requiring the continuous use of outer cortex's reserve glomeruli. According to the hyperfiltration theory, pressures and flows in outer cortical glomeruli contribute to continuous intrarenal capillary hypertension and predispose healthy people to progressive glomerular sclerosis and deterioration of renal function. Pressures and flows associated with the response to renal disease in turn may accelerate the development of sclerosis, leading to even more rapid loss of renal function. Restriction of dietary protein (less than or equal to 0.6 g/kg per day) and/or phosphorus seems to slow the rate of loss of renal function in patients with chronic renal insufficiency. Evidence for the role of lipids in the progression of renal disease is not clear. All of these dietary factors possibly play a role in the progression of renal disease; the relative importance of each factor varies, depending on the pathogenesis, stage, and mechanism of progression of the disease. Findings indicate that nutrition therapy can decrease rate of deterioration of renal function in patients with chronic renal diseases.