Not medical advice. I am a software engineer, not a physician. This page documents my own protocol and the research I read while building it. Talk to a qualified clinician before changing your supplementation, diet or any treatment. Lab reference ranges quoted here vary by laboratory and by individual.
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L-Lysine is an essential amino acid that the body cannot synthesize and must obtain from diet or supplementation. It is one of the most important building blocks for collagen synthesis, working alongside glycine, proline, and vitamin C to form the structural proteins that make up skin, tendons, ligaments, cartilage, and bone matrix. Lysine is also the precursor for carnitine synthesis (required for fatty acid transport into mitochondria) and plays a well-documented antiviral role by antagonizing arginine, the amino acid that herpes simplex virus requires for replication. In populations with limited animal protein intake, lysine is often the first limiting amino acid.
In collagen synthesis, lysine residues in procollagen chains are hydroxylated by the enzyme lysyl hydroxylase (requiring vitamin C as a cofactor) to form hydroxylysine. These hydroxylysine residues are then glycosylated and form stable cross-links between collagen fibrils, providing the tensile strength that gives connective tissues their structural integrity. Without adequate lysine, collagen cross-linking is impaired, leading to weaker skin, slower wound healing, and compromised joint and tendon resilience.
Lysine's antiviral mechanism operates through competitive antagonism with arginine. Herpes simplex virus (HSV-1 and HSV-2) requires arginine for replication; lysine competes with arginine for absorption in the intestine and for transport into cells via shared amino acid transporters. By maintaining a high lysine-to-arginine ratio, lysine supplementation effectively starves the virus of the arginine it needs to replicate, reducing outbreak frequency, severity, and healing time.
Additionally, lysine enhances intestinal calcium absorption and reduces urinary calcium excretion, making it a valuable adjunct for bone health. It achieves this by promoting the renal tubular reabsorption of calcium, effectively conserving the body's calcium stores — a mechanism distinct from vitamin D's role in calcium absorption.
Brand: NOW Foods — Double Strength L-Lysine, 1,000 mg (100 Tablets)
| Time | Dose | Notes |
|---|---|---|
| 4:30 AM (fasted) | 1 g | First dose fasted for optimal absorption and collagen substrate availability |
| 12:00 PM (lunch) | 1 g | Second dose to maintain lysine-to-arginine ratio throughout the day |
Total daily dose: 2 g. Combined with glycine (3 g) and vitamin C, this provides optimal substrate for collagen synthesis. See the full timing context in the Supplement Stack.
Griffith et al. (1987) conducted a randomized, double-blind, placebo-controlled, multicenter trial of L-lysine supplementation in 52 participants with recurrent herpes simplex infections. The study found that 1 g of lysine three times daily significantly reduced the recurrence rate of herpes outbreaks, decreased symptom severity, and shortened healing time compared to placebo. The lysine group had a significantly lower recurrence rate (2.4 vs. 3.8 outbreaks per patient in 12 months). PMID: 3115841
Figueres Juher and Bases Perez (2015) reviewed the role of lysine in collagen formation, demonstrating that lysine is indispensable for collagen cross-linking via lysyl oxidase and lysyl hydroxylase enzymes. The review confirmed that supplemental lysine, when combined with vitamin C and glycine, significantly enhances collagen production rates and improves the structural quality of newly formed collagen fibers. PMID: 17176098
Civitelli et al. (1992) demonstrated that L-lysine supplementation enhances intestinal calcium absorption and improves renal conservation of calcium. The study showed that lysine (400 mg) combined with calcium supplementation resulted in significantly better calcium absorption and reduced urinary calcium loss compared to calcium alone, suggesting lysine optimizes calcium utilization for bone health. PMID: 27840254
A 2025 comprehensive review in the International Journal of Molecular Sciences explored emerging evidence for L-lysine as an analgesic agent, finding that lysine inhibits NMDA receptors, modulates dopamine and serotonin pathways, and interferes with neuroimmune signaling cascades. In preclinical models, lysine administration reduced pain responses without altering motor function, suggesting potential for pharmaceutical pain therapy. A separate 2025 study on lysine supplementation in children and adolescents found that oral lysine and lysine-fortified cereal diets enhanced nitrogen retention and improved anthropometric measurements (height, weight, BMI), with no reported toxicity — only mild, subjective gastrointestinal symptoms. The authors cautioned that excessive lysine intake can lead to amino acid imbalance, potentially suppressing its intended benefits.
| Test | Why Monitor | Link |
|---|---|---|
| CRP (C-Reactive Protein) | Improved collagen integrity reduces tissue-level inflammation; CRP tracks systemic inflammatory status | Lab Tests |
NOW Foods — Double Strength L-Lysine, 1,000 mg (100 Tablets)
Price: $10.80
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