Diacylglycerol (DAG) supplementation has been shown to be associated with the health improvement of patients with diabetes mellitus, although this efficacy is uncertain. We quantitatively examined the effect of dietary DAG on fasting serum glucose and insulin concentrations by conducting a meta-analysis of randomized controlled trials. Potential papers were initially searched from electronic databases of Medline, Embase, and Cochrane Library. Inclusion criteria required the trial to be randomized, with triacylglycerol (TAG) controlled with fasting serum glucose or insulin concentration as one of the end points. Information was extracted independently by two reviewers and the effect of DAG was examined using Review Manager 4.2. Results showed that DAG reduced fasting serum insulin concentration significantly compared with TAG (weighted mean difference [WMD] = -8.23 pmol/l; 95% confidence interval [CI], -15.17 to -1.28 pmol/l; p = 0.02). In addition, DAG supplementation reduced fasting serum glucose concentration greatly (WMD = -0.10 mmol/l; 95% CI, -0.24 to 0.04 mmol/l; p = 0.18), and this effect was significantly correlated with the duration of intervention (fasting serum glucose concentration = 1.075-0.012; duration of intervention; p = 0.04; r = 0.90). In conclusion, DAG supplementation improved fasting serum glucose and insulin concentrations compared with TAG, and the effect on glucose was significantly correlated with the duration of intervention.
Keywords: Diacylglycerols; diabetes; glucose; insulin; meta-analysis.