Poster Topical Area: Energy and Macronutrient Metabolism
Location: Hall D
Poster Board Number: 484
Objective: To assess the effect of low-calorie diets with normal (18%) vs. high (35%) protein (mainly coming from lean animal source) composition on glucose metabolism and adipokines concentration in overweight and obese subjects with type 2 diabetes.
Design: 73 subjects (43.8% men, 55.6±8.37 aged and 32.8±3.67 of BMI) were randomized to follow one of two calorie-restricted diets with the following distribution of calories from protein, carbohydrates and fat, respectively: 18%, 52% and 30%; 35%, 35%, and 30%, during six months. Anthropometric, clinical, biochemical (including adipokines concentration) and dietary and physical activity assessment was performed at baseline and after 3 and 6-months intervention.
Results: Weight loss homogenously decreased among diets. Glycemic control showed a greater improvement regardless of weight loss in subjects consuming 35-%-protein diet, including glucose, insulin, HOMA-IR, and HbA1c. HOMA-IR diminished by -23.4±27.7% and -37.7±21.3 after 3-months (P=0.023 comparing both diets), and -20.6±34.6% and -41.7±18.1% after 6-months (P=0.004) with 18%- and 35%-protein diets, respectively. RBP4 and leptin significantly decreased in both diets although no differences were found between diets. Adiponectin significantly increased in both diets; it changed by 6.05% and 29.9% at 3-months in 18%- and 35%-protein diets, respectively (P=0.167), and 23.7% and 53.5% at 6-months in 18%- and 35%-protein diets, respectively (P=0.219). Adiponectin variation was inversely correlated to HbA1c (R=-0.431, PP=0.043) and HOMA-IR (R=-0.262, P=0.047) changes at 6-months.
Conclusions: A 35%-protein energy-restricted diet lead to a greater glucose metabolism improvement, especially observed in HOMA-IR, irrespective of weight loss. Adiponectin levels showed a higher increase after 35%-protein diet although statistical significance was not found. This change was inversely associated to HbA1c, HOMA-IR and insulin variations. Our findings demonstrate that high-protein diets improve glycemic parameters regardless weight loss in diabetic subjects. However, this effect seems not to be explained by changes in plasma concentrations of adipokines.
This study was supported in part by three grants from the Carlos III Research Institute: CIBERCV (co-supported by the European Regional Development Fund (ERDF) which is allocated by the European Union; IIS16/0114), PI13/02507 and PI15/01983.
Hospital Universitario Miguel Servet, Instituto de Investigación Sanitaria Aragón (IIS Aragón), CIBERCV, Universidad de Zaragoza.
Zaragoza, Aragon, Spain