Short answer: L-Arginine converts directly into nitric oxide, while L-Citrulline recycles back into arginine — a continuous cycle that sustains vessel relaxation and circulation support more consistently than either alone.
L-Arginine: the direct nitric-oxide source
L-Arginine is converted by the body into nitric oxide, relaxing and dilating blood vessels — helping relax blood vessels and improve circulation throughout the body.
L-Citrulline: the sustaining recycler
L-Citrulline supports flexible blood vessels and circulation by being converted into arginine within the body, creating a continuous cycle rather than a single spike in nitric-oxide availability.
Why pairing both makes formulation sense
Combining a direct nitric-oxide source with a recycling precursor is a common, sensible approach in this ingredient category — sustaining circulation support across the day rather than one brief peak.
See both in CardioC2's full formula
Named plainly, alongside six other ingredients.
See the Ingredients