Behavioral Lifestyle Interventions for Weight Loss in Overweight or Obese Patients with Type 2 Diabetes: A Systematic Review of the Literature

Purpose of review: Around 80-90% of patients with type 2 diabetes mellitus (T2DM) are overweight or obese, presenting a greater risk for serious health complications and mortality. Thus, weight loss represents a main goal for T2DM management. Although behavioral lifestyle interventions (BLIs) could help promoting weight loss in T2DM patients with overweight or obesity, their effectiveness is still controversial. This systematic review offers an updated and comprehensive picture of BLIs according to Michie's classification in T2DM patients with overweight or obesity and identifies possible factors (related to both patients and interventions) associated with weight loss. The PRISMA guidelines were followed. The literature search till March 2023 indicated 31 studies involving 42 different BLIs. Recent findings: Our findings suggest that structured BLIs, characterized by frequent feedback and support, can lead to a clinically meaningful 5% weight loss, regardless of specific behavioral, diet, and physical activity components. Further research should address methodological issues and heterogeneity of interventions, also considering the effect of pharmacological therapies on weight reduction. Lastly, more attention should be paid to the long-term effectiveness of behavioral lifestyle interventions and to the relationship between weight loss and diabetes.