INS and type 2 diabetes mellitus: Individuals with T2D on resveratrol supplements had lower fasting glucose levels (SMD: −0.06 [95% CI: −0.24, 0.12]; I2 = 4%, p = 0.39) (Figure 2A) and insulin (SMD: −0.08 [95% CI: −0.50, 0.34], I2 = 73%, p = 0.002), respectively, when compared to those on placebo (Figure 2B).