Acute caloric restriction improves glomerular filtration rate in patients with morbid obesity and type 2 diabetes

Abstract

AimThe role of caloric restriction in the improvement of renal function following bariatric surgery is still unclear; with some evidence showing that calorie restriction can reduce proteinuria. However, data on the impact of caloric restriction on renal function are still lacking. MethodsRenal function, as measured by glomerular filtration rate (GFR), was evaluated in 14 patients with type 2 diabetes mellitus, morbid obesity and stage 2 chronic kidney disease before and after a 7-day very low-calory diet (VLCD). ResultsAfter the VLCD, both GFR and overall glucose disposal (M value) significantly increased from 72.6±3.8mL/min/1.73m−2 BSA to 86.9±6.1mL/min/1.73m−2 BSA (P=0.026) and from 979±107μmol/min1/m2 BSA to 1205±94μmol/min1/m2 BSA (P=0.008), respectively. A significant correlation was observed between the increase in GFR and the rise in M value (r=0.625, P=0.017). ConclusionOur observation of improved renal function following acute caloric restriction before weight loss became relevant suggesting that calory restriction per se is able to affect renal function.