L-Arginine for Blood Pressure Regulation

Research suggests that L-arginine may play a meaningful role in blood pressure regulation, primarily through its function as a precursor to nitric oxide, a molecule that helps blood vessels relax and widen. An umbrella review of seven meta-analyses found modest reductions in both systolic and diastolic blood pressure among adults with hypertension following L-arginine supplementation, though the authors noted significant variability across the underlying studies, limiting the confidence with which firm conclusions can be drawn. Animal research further supports the broader biological plausibility of this mechanism, with studies indicating that disruptions to L-arginine metabolism — such as those caused by reduced kidney mass or elevated levels of ADMA, a compound that blocks nitric oxide production — can raise blood pressure, and that restoring L-arginine availability through supplementation or related pathways may offset those effects. Overall, the evidence base includes a small number of human-focused reviews and a larger body of mechanistic animal research, meaning that while the underlying biology is reasonably well characterized, robust clinical evidence specifically attributing blood pressure benefits to L-arginine supplementation in humans remains limited and mixed.