Applied nutritional investigationA meal replacement regimen improves blood glucose levels in prediabetic healthy individuals with impaired fasting glucose

ObjectiveThe 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.MethodsForty-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/m2) 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.ResultsBoth 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)ConclusionIt 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.