From the Research
Citrulline does not have a significant effect on blood pressure, as evidenced by the most recent and highest quality study. The study published in 2023 1 found that short-term L-citrulline supplementation did not affect blood pressure, pulse wave reflection, or arterial stiffness at rest and during isometric exercise in older males. This study's findings are consistent with some other recent studies, such as the 2018 meta-analysis published in Current Hypertension Reports 2, which found that L-citrulline supplementation had no beneficial effect on blood pressure.
Some key points to consider:
- The 2023 study 1 used a double-blind crossover design and found no significant effects of L-citrulline supplementation on blood pressure.
- The 2018 meta-analysis 2 found that L-citrulline supplementation had no significant effect on brachial systolic and diastolic blood pressure.
- While some studies, such as the 2019 systematic review and meta-analysis 3, suggest that L-citrulline supplementation may reduce systolic blood pressure, the evidence is not consistent across all studies.
- The 2021 study 4 found that supplementation with polyphenol extract and L-citrulline had no impact on ambulatory blood pressure in adults with prehypertension, although it may reduce ambulatory systolic blood pressure in women.
In terms of dosing, typical supplemental doses of citrulline range from 3-6 grams daily, with some studies using up to 9 grams for blood pressure effects. However, the evidence does not support a significant blood pressure-lowering effect of citrulline supplementation. As with any supplement, individuals with low blood pressure, those taking blood pressure medications, or individuals with certain kidney conditions should consult a healthcare provider before using citrulline supplements.