G A Silverii 1, L Botarelli 2, I Dicembrini 2, V Girolamo 2, F Santagiuliana 3, M Monami 3, E Mannucci 2
Main idea: LC diets may produce small short-term improvements in HbA1c and weight, which are not maintained in the long term. Data on their renal safety are insufficient.
Aim: To assess whether LC diets are associated with long-term improvement in glycemic control and weight loss in people with T2DM, and their cardiovascular and renal safety.
Methods: Meta-analysis of randomized controlled trials lasting more than 3 months, retrieved through extensive search on PubMed, Embase, ClinicalTrial.gov, Cochrane databases up to March 1st, comparing LC diets and balanced carbohydrate diets in people with T2DM. Results: We retrieved 37 trials, including 3301 patients. Average carbohydrate intake in LC diets was 36% of total energy. VLC diets were associated with significant HbA1c reduction at 3 and 6 months, but not at 12 and 24 months. No significant differences in body weight, lipid profile, or blood pressure were found in the long term. Only a minority of trials reported data on renal function, so renal safety could not be assessed.