Soy-Protein Consumption and Kidney-Related Biomarkers Among Type 2 Diabetics: A Crossover, Randomized Clinical Trial
published online 16 September 2009.
Objective
Renal disease is a major problem among diabetic patients. The type of protein consumed may affect alterations in kidney-related biomarkers in these patients. This study sought to assess the effects of soy-protein consumption on renal-related markers among type 2 diabetic patients with nephropathy.
Methods
A crossover, randomized clinical trial was conducted among 14 patients (10 men and 4 women). One diet contained 0.8 g/kg protein (70% animal and 30% vegetable proteins), and a similar diet contained the same amount of protein with 35% animal protein, 35% soy protein, and 30% other vegetable proteins. These two diets were prescribed in each phase of the trial for 7 weeks. There was a 4-week washout between the two phases of the study.
Results
Consumption of soy protein reduced urinary urea nitrogen (−0.9 ± 0.8 vs. 0.2 ± 0.6 mg/dL, respectively, SD; P < .001), proteinuria (−78 ± 37 vs. 42 ± 39 mg/day, respectively, SD; P < .001), blood sodium (−2 ± 0.04 vs. 2.0 ± 0.06 mg/dL, respectively, SD; P < .01), and serum phosphorus (−0.03 ± 0.2 vs. 0.2 ± 0.3 mg/dL, respectively, SD; P < .01) compared with animal protein. Serum and urinary creatinine, blood urea nitrogen, serum calcium, and potassium levels were not significantly changed in soy-protein versus anima-protein consumption.
Conclusion
Soy-protein consumption reduces proteinuria in type 2 diabetes with nephropathy.
Department of Nutrition, School of Public Health, and Food Security and Nutrition Research Center, Isfahan University of Medical Sciences, Isfahan, Iran
Address reprint requests to Leila Azadbakht, PhD, Department of Nutrition, School of Public Health, Isfahan University of Medical Sciences, PO Box 81745, Isfahan, Iran.
ABSTRACT