What are olive leaf extract’s main benefits?

Olive leaf extract’s main purported benefit is its effect on cardiovascular health and metabolic health. Some research has found that olive leaf extract reduced blood pressure in people with prehypertension and hypertension^[1] and in the general adult population.^[2] However, the quality of the research was quite low. More recent research found no effect on blood pressure or other markers of cardiometabolic health.^[3] Given the low quality and limited amount of research, olive leaf extract might be beneficial for cardiovascular health, but these findings should be interpreted with caution.