🔑 Core Function

• Nitric oxide synthesis: Precursor for NO → regulates vasodilation and blood pressure.
• ️ Immune defence: Fuels T-cell activity and supports immune response.
• Wound healing: Required for collagen formation and tissue repair.
• Urea cycle: Detoxifies ammonia by converting it into urea for excretion.

🧬 Family & Essentiality

🌿 Plain-Language Summary

Arginine is often called the “blood flow amino acid”. It makes nitric oxide, which relaxes blood vessels to support circulation. It also aids immunity, healing, and nitrogen waste removal. During stress (illness, burns, surgery), dietary arginine needs may increase.

⚗️ Molecular & Chemical IDs

• Abbreviation: Arg / R
• Chemical formula: C₆H₁₄N₄O₂
• Structure: Basic amino acid with guanidino group (positively charged)

⚡ Functions

• Circulation: Arginine → nitric oxide → vasodilation & blood pressure regulation.
• Detoxification: Central to urea cycle → removes ammonia.
• ️ Immunity: Enhances T-cell proliferation & macrophage activity.
• Healing: Collagen synthesis for wound repair.
• Hormonal effects: Stimulates growth hormone, insulin, glucagon.

🍽️ Absorption & Bioavailability

🇦🇺 Australian NRVs (NHMRC)

No specific NRV set for arginine (conditionally essential). Adequate protein intake meets needs in healthy adults.

🥗 Food Sources

• Meat, poultry, fish
• Dairy
• Eggs
• Nuts (peanuts, almonds, walnuts), seeds (pumpkin, sesame), soy products, legumes

Nuts and seeds are particularly rich sources compared to many other amino acids.

🧪 Testing & Monitoring

• Plasma amino acid profiling (specialist use).
• ❌ Not a routine clinical test in Australia.

🔄 Interactions

• ➕ Vitamin C & zinc support arginine’s role in wound healing.
• ⚠️ HSV caution: High-arginine diets may trigger outbreaks; lysine competes with arginine.
• ⚠️ Supplementation may interact with nitrates, antihypertensives, or erectile dysfunction medicines (via vasodilation).

🚨 Deficiency & Evidence

Deficiency

Rare in adults; may occur during growth, prematurity, trauma, or critical illness.

Evidence Snapshot

• ✅ Established: Central to NO production, urea cycle, immunity.
• ⚖️ Clinical research: Arginine-enriched formulas support wound healing & surgical recovery. Evidence for cardiovascular or erectile dysfunction supplementation is mixed.