L-Lysine
Amino Acid ·Exploratory record · not publication-reviewed ·Updated July 13, 2026
Essential amino acid important for collagen synthesis, calcium absorption, and antiviral activity.
Exploratory record, not a reviewed medical publication.
See the editorial and medical-review policies for the publication gate.
This generated database record has not completed a claim-level review by a qualified human medical reviewer. Bibliography links and evidence labels are not approval. The page remains available for reference and is excluded from search indexing.
What the research says.
A quick, data-only summary. The full evidence, dosing, and sources are below.
L-Lysine is an amino acid most often used for cold sore prevention, collagen synthesis, calcium absorption. NutriStack rates the overall evidence as moderate. A typical adult dose is 500-3,000 mg daily, commonly taken as l-lysine hcl. This profile indexes 16 sources.
The bottom line
Evidence rating moderate. Most-documented uses: cold sore prevention, collagen synthesis, calcium absorption. 16 sources indexed (1984–2026), with 0 interaction records on file.
How it works, mechanistically.
Core mechanism
Required for collagen cross-linking (hydroxylysine). Competes with arginine for cellular uptake, inhibiting HSV replication. Supports carnitine synthesis and calcium absorption.12,7
Dosing & protocol.
What it actually costs.
Real-world pricing across three quality tiers. Assumes L-Lysine HCl.
Assumes 500-3,000 mg/day. Vendor basis: NOW/iHerb, Vitacost, BulkSupplements powder, and Amazon marketplace; powder is the budget tier. Updated 2026-05-28.
The same dose, as food.
How much you'd eat to match a supplemental dose.
Whole proteins are usually a practical lysine source.
Full safety detail.
Side effects
- GI upset
- Diarrhea at high doses
Contraindications
- Kidney disease
- Liver disease
Sources, by evidence tier.
Numbered references. Citations throughout the page link here.
Meta-analyses & systematic reviews
3- 1Lysine requirements of finishing boars and gilts: A meta-analysisPMIDAymerich P, Tokach MD, Dritz SS et al. · Animal : an international journal of animal bioscience · 2021
Aymerich P, Tokach MD, Dritz SS et al.. Lysine requirements of finishing boars and gilts: A meta-analysis. Animal : an international journal of animal bioscience. 2021
- 2The Safety and Efficacy of Lysine Analogues in Cancer Patients: A Systematic Review and Meta-AnalysisPMIDMontroy J, Fergusson NA, Hutton B et al. · Transfusion medicine reviews · 2017
Montroy J, Fergusson NA, Hutton B et al.. The Safety and Efficacy of Lysine Analogues in Cancer Patients: A Systematic Review and Meta-Analysis. Transfusion medicine reviews. 2017
- 3Meta-analysis of milk protein yield responses to lysine and methionine supplementationPMIDVyas D, Erdman RA · Journal of dairy science · 2009
Vyas D, Erdman RA. Meta-analysis of milk protein yield responses to lysine and methionine supplementation. Journal of dairy science. 2009
Randomized controlled trials
4- 4Milk Protein Glycation Compromises Postprandial Lysine Bioavailability but does not Modulate Postprandial Muscle Protein Synthesis Rates In Vivo in Males: A Double-blind, Randomized Parallel TrialPMIDvan Lieshout GAA, Trommelen J, Hendriks FK et al. · The Journal of nutrition · 2025
van Lieshout GAA, Trommelen J, Hendriks FK et al.. Milk Protein Glycation Compromises Postprandial Lysine Bioavailability but does not Modulate Postprandial Muscle Protein Synthesis Rates In Vivo in Males: A Double-blind, Randomized Parallel Trial. The Journal of nutrition. 2025
- 5L-lysine and L-arginine supplementation modifies the anxiety response to stress in humansSource linkedPMIDSmriga M, Ando T, Akutsu M et al. · Biomed Res · 2007
- 6Dietary L-lysine and calcium metabolism in humansPMIDCivitelli R et al. · Nutrition · 1992
L-lysine significantly increased intestinal calcium absorption and improved renal conservation of absorbed calcium, suggesting usefulness for osteoporosis prevention.
- 7Lysine prophylaxis in recurrent herpes simplex labialis: a double-blind, controlled crossover studyPMIDThein DJ et al. · Oral Surg Oral Med Oral Pathol · 1984
When serum lysine concentration exceeded 165 nmol/ml there was a significant decrease in HSV recurrence rate, suggesting prophylactic benefit at adequate serum levels.
Reviews & position papers
7- 8Comprehensive Review of L-Lysine: Chemistry, Occurrence, and Physiological RolesPMIDHashim M, Alam I, Ahmad M et al. · Current protein & peptide science · 2026
Hashim M, Alam I, Ahmad M et al.. Comprehensive Review of L-Lysine: Chemistry, Occurrence, and Physiological Roles. Current protein & peptide science. 2026
- 9Lysine-Specific Demethylase 1 Inhibitors: A Comprehensive Review Utilizing Computer-Aided Drug Design TechnologiesPMIDHan D, Lu J, Fan B et al. · Molecules (Basel, Switzerland) · 2024
Han D, Lu J, Fan B et al.. Lysine-Specific Demethylase 1 Inhibitors: A Comprehensive Review Utilizing Computer-Aided Drug Design Technologies. Molecules (Basel, Switzerland). 2024
- 10L-lysine: Its antagonism with L-arginine in controlling viral infection. Narrative literature reviewPMIDPedrazini MC, da Silva MH, Groppo FC · British journal of clinical pharmacology · 2022
Pedrazini MC, da Silva MH, Groppo FC. L-lysine: Its antagonism with L-arginine in controlling viral infection. Narrative literature review. British journal of clinical pharmacology. 2022
- 11Comprehensive Safety Assessment of l-Lysine Supplementation from Clinical Studies: A Systematic ReviewPMIDHayamizu K et al. · Nutrients · 2020
L-lysine supplements are clinically safe with no reported toxicity; adverse events limited to subjective GI symptoms. NOAEL is 6000 mg/person/day.
- 12Protein, lysine and vitamin D: critical role in muscle and bone healthPMIDVeldurthy V et al. · Curr Opin Clin Nutr Metab Care · 2020
Lysine along with protein and vitamin D play critical roles in muscle and bone health; lysine is essential for collagen cross-linking and calcium absorption.
- 13Lysine for Herpes Simplex Prophylaxis: A Review of the EvidencePMIDChi CC et al. · Integr Med (Encinitas) · 2019
L-lysine supplementation appears to be ineffective for HSV prophylaxis at doses less than 1 g/day without low-arginine diet; higher doses with dietary modification may be beneficial.
- 14Safety assessment of L-lysine oral intake: a systematic reviewPMIDHayamizu K et al. · Amino Acids · 2019
Review of 71 articles (3357 subjects) with doses up to 17.5 g/day found L-lysine safe with gastrointestinal symptoms as only side effects; provisional NOAEL of 6000 mg/day.
Reference material
2- 15Matthews DE. Review of Lysine Metabolism with a Focus on Humans. The Journal of nutrition. 2020Source linkedPMID
- 16Gunarathne R, Guan X, Feng T et al.. L-lysine dietary supplementation for childhood and adolescent growth: Promises and precautions. Journal of advanced research. 2025Source linkedPMID
Common questions.
Quick answers about L-Lysine, drawn from the data on this page.
What is L-Lysine?
Essential amino acid important for collagen synthesis, calcium absorption, and antiviral activity.
What is L-Lysine used for?
Commonly cited benefits of L-Lysine include: Cold sore prevention; Collagen synthesis; Calcium absorption; Immune support. NutriStack rates the overall evidence as moderate.
What is a typical dose of L-Lysine?
A typical adult dose of L-Lysine is 500-3,000 mg daily. The commonly recommended form is L-Lysine HCl. These are general ranges, not personalized advice; confirm the right dose with a clinician.
What are the side effects of L-Lysine?
Reported side effects include gi upset, diarrhea at high doses. This is educational information; check with a healthcare professional before use.
How strong is the evidence for L-Lysine?
NutriStack rates this as Moderate, meaning several aligned RCTs or one large RCT plus supporting reviews. Full tier criteria are at https://nutristackapp.com/methodology/evidence-tiers.
Use this with your stack
L-Lysine in NutriStack.
Add it to your stack, see how it interacts with everything else you take, and get a Stack Score that updates the moment it does.