INS and metabolic syndrome: For instance, supplementation with Olive leaf and fruit extracts (100 mg/day oleuropein and 20 mg/day hydroxytyrosol) significantly decreased FBG by 4.8% over 2 months (35), while Olive leaf polyphenols (51.1 mg oleuropein and 9.7 mg hydroxytyrosol per day) for 3 months enhanced insulin sensitivity and β-cell function in overweight men at risk of metabolic syndrome (19).