Effect of steviol glycosides as natural sweeteners on glucose metabolism in adult participants.

Steviol glycosides (SGs) are recognized as safe natural sweeteners; however, evidence from randomized controlled trials (RCTs) showed an inconclusive effect of SGs on glucose metabolism in adult participants. We aimed to conduct a systematic review and meta-analysis of RCTs to assess the effect of SGs on glucose metabolism. We systematically searched PubMed, Web of Science and EMBASE to include eligible RCTs. Our primary outcomes were differences between SGs and the control group with respect to changes in blood glucose from the baseline to the end of intervention (including fasting blood glucose [FBG], and HbA1c measurements). A random-effects meta-analysis was conducted for data synthesis to calculate the pooled mean difference (MD). There were twelve RCTs included for analyses with a total of 871 participants (48% females). A significant effect of SGs on FBG (MD = -4.10 mg dl-1, 95% CI -6.55 to -1.65) was found, while no significant difference in HbA1c (MD = 0.01%, 95% CI -0.12% to 0.13%) was observed between SGs and controls. The whole quality of evidence was rated as low. Subgroup analyses demonstrated favorable effects of SGs on FBG in participants aged ≤50 years, those without diabetes mellitus (DM) or hypertension at the baseline, and overweight and obese adults. Sensitivity analyses yielded results largely similar to the main findings. To conclude, SGs are found to produce significant improvement in glucose metabolism in adult participants when compared with the control. More evidence is required to further clarify and support the benefit of SGs as a sugar substitute for glucose metabolism.