Your muscles need oxygen, nutrients, and blood flow delivered at the right time - and nitric oxide is the molecule that makes it happen. A natural vasodilator produced by the body, nitric oxide signals blood vessels to relax and widen, improving circulation to working muscles during exercise. Total Nitric Oxide from Onnit is formulated to support your body's own NO production, using a research-backed combination of L-Citrulline, Beet Root, and supporting compounds.

The result: better pumps, improved endurance, faster recovery, and more efficient oxygen delivery when you need it most.

Beyond athletic performance, nitric oxide plays a well-documented role in sexual health. The same vasodilation mechanism that improves blood flow to muscles also supports erectile function - nitric oxide is the primary signalling molecule responsible for smooth muscle relaxation in penile tissue, a mechanism that underpins how most prescription ED medications work at a physiological level (PMID: 17143052). For men looking to support both gym performance and sexual health through the same pathway, Total Nitric Oxide addresses both simultaneously.

Key ingredients and the science behind them:

L-Citrulline is converted to L-Arginine in the kidneys, which then serves as the direct precursor to nitric oxide synthesis. Supplementing with citrulline has been shown to be more effective at raising plasma arginine levels than arginine supplementation itself, supporting both aerobic and anaerobic performance (PMID: 20386132).

Beetroot (Beta vulgaris) is naturally rich in dietary nitrates, which the body converts to nitric oxide via the nitrate-nitrite-NO pathway. Research shows beetroot supplementation can reduce the oxygen cost of exercise and improve time-to-exhaustion (PMID: 19661447).

L-Arginine AKG (Alpha-Ketoglutarate) provides a further substrate for nitric oxide production while also supporting energy metabolism during high-intensity training (PMID: 16923826).

Vitamin C plays a supporting role in protecting nitric oxide from oxidative breakdown, helping to maintain bioavailable NO levels during and after exercise (PMID: 12527670).

Supply: 236g tub, 20 servings. Mix one scoop with water and take before training.

Stocked and shipped from Dublin. Order before 4pm for same-day dispatch.