Three loose routes: circulation via L-citrulline and nitric oxide, cellular energy via L-carnitine and niacin, and antioxidant and general support from four plant extracts. Zinc sits underneath as a mineral involved in hormone metabolism.
Every rationale below comes from research on an ingredient studied on its own, at a stated dose. This product discloses a 570 mg blend total without saying how it splits, so none of that research can be connected to what is actually in a capsule. That limitation runs through this whole page.
L-citrulline is a precursor to nitric oxide, a vasodilator that relaxes blood vessels and improves blood flow. It has the most developed research of the six blend ingredients on this route.
The body converts citrulline to arginine, mainly in the kidneys, and arginine feeds nitric oxide production. Oral citrulline raises arginine levels more effectively than oral arginine does, which is why it has largely replaced arginine in this kind of formula. Published work typically uses doses measured in grams — well above what a shared 570 mg blend can deliver.
Pine bark and grape skin extracts contribute polyphenols also studied in circulatory contexts, though the human evidence for resveratrol in particular has proved harder to replicate than early laboratory results suggested.
Niacin converts in the body to NAD, a coenzyme central to how cells release energy from food. L-carnitine transports fatty acids into cells to be burned as fuel.
Both are real, well-characterised mechanisms rather than marketing constructs. Niacin at 20 mg is a properly dosed amount — it is one of the two ingredients here whose quantity you can actually check.
Zinc is involved in testosterone synthesis pathways and in immune function. Maca and saffron carry small-trial evidence around mood, energy and general vitality.
The zinc caveat matters: population research links zinc deficiency to lower testosterone, but supplementation research in men who are already zinc-replete shows much more mixed results. If your zinc status is fine, adding more is unlikely to move anything.
Maca's evidence base is genuine but consists of small studies with mixed results. Saffron's sits mostly around mood. Neither should be read as a strong claim. See each ingredient in detail →