What do cardiovascular health, athletic performance, and male sexual function have in common? They all depend on healthy circulation! And the key to healthy circulation is healthy blood vessels. Just like water through a garden hose, blood flows best through your blood vessels when they are flexible and relaxed.

Many people reach for arginine supplements because this amino acid boosts production of nitric oxide in the body — and nitric oxide helps relax the blood vessels. But that’s not the best strategy. Why? Because arginine is broken down by the enzyme arginase before it can reach the bloodstream. As a result, barely any arginine you ingest is actually absorbed. That’s where citrulline comes in.

Citrulline helps your body make arginine. Research shows that supplementing with citrulline raises arginine levels 2.3 times more effectively than taking arginine itself. But conventional citrulline products have two problems. First, they contain large citrulline particles that can’t be absorbed completely. Second, their contents are released all at once, so they don’t stay in the bloodstream long.

Luckily, there’s Citrulline-SR from Quality of Life. Citrulline-SR features MicroActive® Citrulline, a special micronized form of citrulline that is better absorbed than regular citrulline. Because it delivers sustained release over 10 hours, Citrulline-SR consistently elevates blood levels of the compound.