Calorie-restricted diet may prolong T2D remission

A diet with calorie restriction appears helpful for type 2 diabetes (T2D) remission, particularly when done along with an intensive lifestyle modification program, suggests a recent study.

A team of investigators searched the databases of PubMed, Scopus, Central, Web of Science, and gray literature until November 2022 for randomized trials >12 weeks assessing the effect of a prespecified calorie-restricted diet on T2D remission.

Random-effects meta-analyses were conducted to estimate the absolute effect (risk difference) at 6- and 12-month follow-ups. Dose‒response meta-analyses were also carried out to estimate the mean difference (MD) for the effects of calorie restriction on cardiometabolic outcomes. The investigators used the GRADE* approach to evaluate the certainty of evidence.

Twenty-eight trials including a total of 6,281 participants met the eligibility criteria.

Using a remission definition of a glycated haemoglobin (HbA1c) level of <6.5 percent without antidiabetic medication use, calorie-restricted diets resulted in increased remission by 38 more per 100 patients (95 percent confidence interval [CI], 9‒67; n=5 trials; GRADE=moderate) at 6 months and by 13 more per 100 patients (95 percent CI, 10‒18; n=4; GRADE=moderate) at 12 months when compared with usual diet or usual care.

Using a definition of HbA1c of <6.5 percent after at least 2-month cessation of antidiabetic medications, remission improved to 34 more per 100 patients (95 percent CI, 15‒53; n=1; GRADE=very low) at 6 months and by 16 more per 100 patients (95 percent CI, 4‒49; n=2; GRADE=low) at 12 months.

Notably, each 500-kcal/day reduction in energy intake led to clinically significant decreases in body weight (MD, ‒6.33 kg, 95 percent CI, ‒7.76 to ‒4.90; n=22; GRADE=high) and HbA1c (MD, ‒0.82 percent, 95 percent CI, ‒1.05 to ‒0.59; n=18; GRADE=high). This reduction eased at 12 months.

*Grading of Recommendations Assessment, Development, and Evaluation