Objective: The aim of this study was to investigate the effect of a 6-wk intervention with either lifestyle intervention (increased physical activity and a low-calorie diet) or a meal replacement regimen on glycemic control in patients who are prediabetic and have impaired fasting glucose.
Methods: Forty-two overweight or obese men and women (age 54 ± 8 y; weight 95.1 ± 11.9 kg; body mass index [BMI] 32.8 ± 2.89 kg/m(2)) were included in this randomized controlled clinical trial. Patients in the lifestyle group (LS; n = 14) received dietary counseling sessions (fat-restricted low-calorie diet) and instructions on how to increase physical activity. Patients in the meal replacement group (MR; n = 28) were instructed to replace two daily meals with a low-calorie, high soy-protein drink with a low glycemic index.
Results: Both interventions resulted in a significant decrease in body weight and BMI, although the reduction was more pronounced (P < 0.05) in the MR group. In both groups, glucose concentrations decreased significantly (LS: -12 mg/dL, P < 0.01; MR: -11 mg/dL, P < 0.01), and mean glucose levels returned to the normal range. Insulin (LS: -1 μU/mg [not significant]; MR: -6.3 μU/mg, P < 0.01) and homeostasis model assessment of insulin resistance (HOMA-IR; LS -0.92, P < 0.01; MR: -2.1, P < 0.01) were also significantly lower following both interventions; again improvements were more pronounced in the MR group (insulin: P < 0.05; HOMA P < 0.01) CONCLUSION: It can be concluded that meal replacement is an effective intervention for rapid improvement of elevated fasting glucose and increased insulin concentrations, these being important biomarkers of the prediabetic state. The 6-wk intervention has shown that the effect of meal replacement on fasting blood glucose was comparable to the effect of lifestyle intervention. The alterations in BMI, insulin, and HOMA-IR were significantly more pronounced following the meal replacement regimen.
Keywords: Glycemic index; Lifestyle intervention; Meal replacement; Prediabetes; Protein supplementation.
Copyright © 2014 Elsevier Inc. All rights reserved.