Short answer: L-citrulline and L-arginine are amino acids the body converts into nitric oxide, a molecule that signals blood vessels to relax and widen — a genuine, well-studied mechanism relevant to healthy circulation.
How the nitric oxide pathway actually works
Nitric oxide is produced by cells lining blood vessels and triggers the surrounding muscle to relax, widening the vessel — a process called vasodilation. Wider, more flexible blood vessels allow blood to flow more freely, supporting oxygen and nutrient delivery throughout the body.
Why L-citrulline and L-arginine are often paired
L-arginine converts directly into nitric oxide, but a significant portion is broken down before reaching circulation. L-citrulline converts to L-arginine in the kidneys, providing a more sustained supply — pairing both is a reasonable strategy to support the pathway from two angles.
What "vascular flexibility" actually means
Blood vessels that respond well to nitric oxide signaling — widening and narrowing appropriately — are generally associated with healthier circulation than stiffer, less responsive vessels. This flexibility is influenced by age, activity level, and diet, alongside genetic factors.
See CardioC2's nitric-oxide pathway ingredients
L-citrulline and L-arginine, fully disclosed.
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