INTRODUCTION/OBJECTIVES: Widespread opinion is that hypercaloric foods with high glycemic index induce insulin resistance (IR) and initialize the steps of liver damage. However recent reports have focused on the role of high protein intake in the pathogenesis of type 2 diabetes. AIMS & METHODS: To investigate the dietary habit in a group of obese subjects and to compare the nutrient intake with relation to IR state. Sixty obese patients (23 M/37 F; age 19-62 y) were admitted to the study. Exclusion criteria were HBV(+), HCV(+), alcohol consumption >30 g/day. Dietary habits were recorded by detailed questioning and a computed database determined the nutrient intakes, according to Italian table of food composition. The recommended dietary allowances (RDA) for the Italian population were used for references, set at the highest limit (comparisons with the dietary habits of obese pts.). IR was calculated by the homeostasis model assessment (HOMA). HOMA > 2.5 indicates IR state. Statistical analysis was performed with SPSS 18.0 software (SPSS, Chicago, IL, USA). RESULTS: BMI ranged from 31 to 73 kg/m2 and HOMA was 4.2±2.7. HOMA-IR > 2.5 was observed in 40/60 patients. At US hepatosteatosis was observed in 72%. The comparison of nutrient intake with RDA showed a significant difference (p < 0.001) for protein, animal protein and fat, whereas carbohydrate intake did not significantly differ. The comparisons between the two group with and without IR showed significant differences of nutrient amounts (g) with relation to the following intakes: total protein (128±26 vs 108±31, p < 0.01), animal protein (81±27 vs 67±26, p < 0.05), fat (166±53 vs 137±50, p < 0.05). Total carbohydrate intake did not differ (430±107 vs 378±130, p = 0.10), as well as simple carbohydrate (113.8±60.4 vs 123.6±79.9, p = 0.6). Odds ratios were calculated for the nutrient daily intakes with relation to IR. Among the excessive nutrient intakes (higher than cut-off) animal protein (>70 g) showed the significant (p < 0.05) risk for IR (OR 3.43, 95% CI = 1.15-10.20). CONCLUSION: Diets with excessive intake of animal protein are associated with an increased risk of insulin resistance. Carbohydrate intake, even if not elevated, would maintain and enhance IR, favouring the progression of liver steatosis, inflammation and fibrosis.
ARE INSULIN RESISTANCE AND LIVER STEATOSIS ASSOCIATED WITH HIGH PROTEIN INTAKE IN OBESE SUBJECTS ?
RICCI, Giorgio;CANDUCCI, Edgardo;ALVISI, Vittorio
2010
Abstract
INTRODUCTION/OBJECTIVES: Widespread opinion is that hypercaloric foods with high glycemic index induce insulin resistance (IR) and initialize the steps of liver damage. However recent reports have focused on the role of high protein intake in the pathogenesis of type 2 diabetes. AIMS & METHODS: To investigate the dietary habit in a group of obese subjects and to compare the nutrient intake with relation to IR state. Sixty obese patients (23 M/37 F; age 19-62 y) were admitted to the study. Exclusion criteria were HBV(+), HCV(+), alcohol consumption >30 g/day. Dietary habits were recorded by detailed questioning and a computed database determined the nutrient intakes, according to Italian table of food composition. The recommended dietary allowances (RDA) for the Italian population were used for references, set at the highest limit (comparisons with the dietary habits of obese pts.). IR was calculated by the homeostasis model assessment (HOMA). HOMA > 2.5 indicates IR state. Statistical analysis was performed with SPSS 18.0 software (SPSS, Chicago, IL, USA). RESULTS: BMI ranged from 31 to 73 kg/m2 and HOMA was 4.2±2.7. HOMA-IR > 2.5 was observed in 40/60 patients. At US hepatosteatosis was observed in 72%. The comparison of nutrient intake with RDA showed a significant difference (p < 0.001) for protein, animal protein and fat, whereas carbohydrate intake did not significantly differ. The comparisons between the two group with and without IR showed significant differences of nutrient amounts (g) with relation to the following intakes: total protein (128±26 vs 108±31, p < 0.01), animal protein (81±27 vs 67±26, p < 0.05), fat (166±53 vs 137±50, p < 0.05). Total carbohydrate intake did not differ (430±107 vs 378±130, p = 0.10), as well as simple carbohydrate (113.8±60.4 vs 123.6±79.9, p = 0.6). Odds ratios were calculated for the nutrient daily intakes with relation to IR. Among the excessive nutrient intakes (higher than cut-off) animal protein (>70 g) showed the significant (p < 0.05) risk for IR (OR 3.43, 95% CI = 1.15-10.20). CONCLUSION: Diets with excessive intake of animal protein are associated with an increased risk of insulin resistance. Carbohydrate intake, even if not elevated, would maintain and enhance IR, favouring the progression of liver steatosis, inflammation and fibrosis.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
