NOW Foods L-Citrulline is a dietary supplement that supports nitric oxide production, helping you boost blood flow, lift exercise performance, and recover quicker. The star ingredient, L-Citrulline, acts as a precursor to nitric oxide and supports protein metabolism and ammonia removal in the body. NOW Foods backs quality with GMP manufacture, tight in-house testing, and third‑party audits to keep purity and potency high.

Available Sizes & Variants:

120 tablets dietary supplement – a convenient daily dose for steady support.

Benefits & Features:

• Supports nitric oxide production to help improve blood flow and workout performance.
• Aids ammonia removal and protein metabolism.
• For daily use, this supplement keeps steady nitric oxide support throughout workouts.
• Quality is guaranteed through GMP manufacturing and thorough third party testing.
• Designed for active people, this extra strength formula slots neatly into daily routines and supports oxygen and nutrient transport to aid post workout recovery and keep you moving.

NOW Foods has built a long standing reputation for purity and transparency. L-Citrulline raw materials are tested for purity, heavy metals and microbes, with a minimum purity of 99% targeted. The company documents country of origin and processing locations for each ingredient, ensuring traceability, and uses in-house and mobile dockside testing to safeguard quality. The manufacturing facilities meet GMP standards and are regularly audited by third parties such as Intertek, earning an 'A' rating from the National Products Association for consistent safety and reliability. It sits well with amino acid supplements and some athletes even pair it with creatine monohydrate for a complete performance toolkit.

L-Citrulline

• GTIN: 733739001160
• Manufacturer: NOW Foods
• Categories: CitrullineEndurance SupplementsEnergy Vitamins, Supplements & TabletsNitric Oxide BoostersNOW Foods
• Best buy: 6 - 24 months+

United Kingdom Shipping:

Orders placed by 2pm (Monday to Friday) are dispatched the same day. Orders placed after 2pm will be dispatched the next working day.

Free shipping on orders over £50 to the UK.

Returns: Our products are meant to make you feel healthy and at your best. If you need to return your item, you can do so free of charge within 30 days in the same original and unopened packaging. Subject to T&C's.

Take 1 tablet 1 to 2 times daily between meals. Store in a cool, dry, and dark place after opening. Only for adults. Consult your doctor if you are pregnant, nursing, taking medications (especially blood pressure medications and nitrates or other vasodilators), or have a medical condition (especially abnormal blood pressure). Keep out of reach of children.

Please consult the product packaging for accurate instructions on how to use the product.

*Percent Daily Values are based on a 2,000 calorie diet. Your daily values may be higher or lower depending on your calorie needs.

The Active Ingredient Is: L-Citrulline

L-Citrulline is an non-essential amino acid that acts as an intermediate in the urea cycle and as a precursor to L-arginine, which supports the body’s production of nitric oxide.

This form and ingredient are sourced as a single amino acid designed for purity and quality assurance in supplement production.

What Does L-Citrulline Do?

L-Citrulline is involved in supporting normal blood flow through its role in nitric oxide production, a mechanism linked to vascular function and metabolic health. This connection is supported by researchers looking at how vasodilation operates in humans.

Dr. Schwedhelm of the University of Duisburg-Essen found that L-Citrulline can influence endothelial function and exercise-related blood flow and recovery in adults.

This information aligns with EFSA-style reasoning on how amino acids can participate in normal physiological processes without implying disease-related outcomes.

Compliance note: This product is not intended to diagnose, treat, cure, or prevent any disease.

NOW Foods is our chosen supplier for L-Citrulline because this brand operates at exceptional facility standards, with GMP-compliant production and regular third-party audits that reinforce ongoing quality. This brand stands out for its commitment to transparency and traceability, documenting ingredient country of origin and processing locations and maintaining rigorous in-house testing at every stage. This brand vs alternatives highlights a proven dedication to purity and potency, underpinned by a robust supply chain and ongoing quality assurance practices.

The manufacturer’s ingredient selection philosophy emphasises purity, identity, strength and contamination controls, which aligns with our demand for trustworthy sourcing. Their testing protocols and certifications, including external validations, support a trustworthy quality journey our rigorous testing protocols. The product fit is compelling because L-Citrulline is the sole active ingredient, with a minimal, well-defined profile and high purity targets, making NOW Foods an ideal partner for this supplement. Our team evaluated them with input from our team of medical experts to ensure alignment with our standards.