Weight loss diets improve renal function in obese

(HealthDay)—Low-fat, Mediterranean, and low-carbohydrate diets are similarly effective in improving renal function in moderately obese people with or without type 2 diabetes, according to a study published online May 20 in Diabetes Care.

Amir Tirosh, M.D., Ph.D., from Brigham and Women's Hospital in Boston, and colleagues randomly assigned 318 moderately obese subjects (body mass index, 31 kg/m²) with or without type 2 diabetes to low-fat, Mediterranean, or low-carbohydrate diets for two years and assessed changes in urinary microalbumin and estimated glomerular filtration rate (eGFR).

The researchers found that all three diets were effective in significantly improving eGFR, ranging from an increase of 4.0 to 5.3 percent. The improvement was 6.7 percent for those with diabetes, 4.5 percent for those without diabetes, 7.1 percent for those with lower baseline renal function, and 3.7 percent for those with better baseline renal function. After adjusting for a number of factors, only a decrease in fasting insulin and systolic blood pressure were significantly associated with increased eGFR. All three diets were found to be associated with a similar improvement in the urine microalbumin-to-creatinine ratio.

"In conclusion, we found that dietary interventions to reduce weight cause progressive improvement in eGFR and marked regression of microalbuminuria regardless of the dietary approach," Tirosh and colleagues write.