Proteinuria and renal function in diabetic patients fed a diet moderately restricted in protein

Protein restriction has been used in the treatment of renal disease and may also be beneficial in the management of diabetic nephropathy. We evaluated the effects of moderate protein restriction (0.6 g/kg ideal body weight per day) for a 3-mo period on renal function in seven diabetic patients. Moderate protein restriction led to a decrease of approximately 50% in the albumin excretion rate in patients with overt proteinuria or microalbuminuria. This decrease occurred in some patients without a decrease in glomerular filtration rate, renal plasma flow, or plasma albumin concentration and may reflect subtle changes in filtration properties or permeability of glomeruli. In this pilot study moderate protein restriction has marked effects on albumin excretion irrespective of the initial degree of renal impairment. It is therefore suitable for longer-term study of its effects on the progression of renal disease in both patients with overt and incipient diabetic nephropathy.