L-Lysine Research
40 peer-reviewed studies · Evidence score: 7/10
Nutraceuticals and phytoceuticals in the treatment of schizophrenia: a systematic review and network meta-analysis "Nutra NMA SCZ"
Fornaro M et al. • Molecular psychiatry (2025)
The Author(s), under exclusive licence to Springer Nature Limited.
- Change (Standardized Mean Difference = SMD) in total symptomatology and acceptability (Risk Ratio = RR) were co-primary outcomes.
- High heterogeneity (tau2 = 0.10, I2 = 55.9%) and global inconsistency (Q = 40.79, df = 18, p = 0.002) emerged without publication bias (Egger's test, p = 0.42).
- Sarcosine improved negative symptoms (SMD = -0.65, 95%CI = -1.10; -0.19).
Metabolomics in Diabetic Retinopathy: A Systematic Review
Hou XW et al. • Investigative ophthalmology & visual science (2021)
This review summarizes potential biomarkers and metabolic pathways, providing insights into new pathogenic pathways for this microvascular complication of diabetes.
- This review summarizes potential biomarkers and metabolic pathways, providing insights into new pathogenic pathways for this microvascular complication of diabetes.
- Published in Investigative ophthalmology & visual science (2021)
- Further research warranted to confirm findings
The Impact of Amino Acids on Postprandial Glucose and Insulin Kinetics in Humans: A Quantitative Overview
Sloun BV et al. • Nutrients (2020)
The extracted information is publicly available and can serve multiple purposes such as computational modeling.
- Oral ingestion of most individual AAs induced an insulin response, but did not alter glucose concentrations in healthy participants.
- Specific AAs (i.e., leucine and isoleucine) co-ingested with glucose exerted a synergistic effect on the postprandial insulin response and attenuated the glucose response compared to glucose intake alone in healthy participants.
- Oral AA ingestion as well as intravenous AA infusion was able to stimulate an insulin response and decrease glucose concentrations in T2DM and obese individuals.
Safety assessment of L-lysine oral intake: a systematic review
Hayamizu K et al. • Amino acids (2019)
Integrated analysis of the risk for developing gastrointestinal symptoms revealed that the risk ratio was 1.02 (95% CI, 0.96-1.07; p = 0.49); thus, no significant increase was observed. (UMIN000028914).
- Integrated analysis of the risk for developing gastrointestinal symptoms revealed that the risk ratio was 1.02 (95% CI, 0.96-1.07; p = 0.49); thus, no significant increase was observed. (UMIN000028914).
- The dose range of L-lysine in the selected studies was 16.8-17,500 mg/day, and the range of dosing period was 1-1095 days.
- The observed adverse events were mainly subjective symptoms related to the gastrointestinal tract such as nausea, stomachache, and diarrhea.
Nutritional and herbal supplements for anxiety and anxiety-related disorders: systematic review
Lakhan SE et al. • Nutrition journal (2010)
Based on the available evidence, it appears that nutritional and herbal supplementation is an effective method for treating anxiety and anxiety-related conditions without the risk of serious side effects.
- Of the randomized controlled trials reviewed, 71% (15 out of 21) showed a positive direction of evidence.
- Based on the available evidence, it appears that nutritional and herbal supplementation is an effective method for treating anxiety and anxiety-related conditions without the risk of serious side effects.
- There is the possibility that any positive effects seen could be due to a placebo effect, which may have a significant psychological impact on participants with mental disorders.
Comprehensive Safety Assessment of l-Lysine Supplementation from Clinical Studies: A Systematic Review
Hayamizu K et al. • The Journal of nutrition (2020)
The provisional no-observed-adverse-effect level in healthy human subjects was based on gastrointestinal symptoms and identified at 6.0 g/d.
- The observed adverse events were mainly subjective gastrointestinal tract symptoms; however, the risk analysis for incidence of gastrointestinal symptoms was not statistically significant (risk ratio of 1.02).
- The provisional no-observed-adverse-effect level in healthy human subjects was based on gastrointestinal symptoms and identified at 6.0 g/d.
- The review protocol was registered at umin.ac.jp as UMIN000028914 before the beginning of the study.
Lysine for Herpes Simplex Prophylaxis: A Review of the Evidence
Mailoo VJ et al. • Integrative Medicine (2017)
Doses >3g/day improved patients' subjective disease experience; <1g/day was ineffective.
- Higher doses (>3g) more effective
- Low doses (<1g) ineffective
- Best combined with low-arginine diet
Effects of additional oral fosravuconazole l-lysine ethanolate therapy following inadequate response to initial treatment for onychomycosis: A multicenter, randomized controlled trial
Naka W et al. • The Journal of dermatology (2024)
A high complete cure rate is possible without additional F-RVCZ treatment when nail involvement decreases by ≥55% at week 24; however, when the reduction is <55% at week 24, additional F-RVCZ treatment should be considered to improve the cure rate.© 2024 Japanese Dermatological Association.
- Fosravuconazole l-lysine ethanolate (F-RVCZ), a fourth-generation azole antifungal agent with potent antifungal activity and few drug interactions, was highly effective in a clinical trial, with a complete cure rate of 59.4% at 48 weeks after treatment initiation.
- Patients who demonstrated ≥55% reduction in nail involvement ratio at week 24 were included in Group X and followed up.
- Patients with <55% reduction were randomly assigned to follow-up (Group A) or additional treatment (Group B) groups.
Efficacy and safety of fosravuconazole L-lysine ethanolate, a novel oral triazole antifungal agent, for the treatment of onychomycosis: A multicenter, double-blind, randomized phase III study
Watanabe S et al. • The Journal of dermatology (2018)
The Journal of Dermatology published by John Wiley & Sons Australia, Ltd on behalf of Japanese Dermatological Association.
- The efficacy and safety of F-RVCZ, compared with a placebo, were investigated in a multicenter, double-blind, randomized study of Japanese onychomycosis patients with 25% or more clinical involvement of the target toenail.
- The primary end-point was the rate of complete cure (clinical cure [0% clinical involvement of the target toenail] plus mycological cure [negative potassium hydroxide examination]) at week 48 (36-week post-treatment visit).
- The complete cure rate at week 48 was significantly higher with F-RVCZ (59.4%, 60/101) than the placebo (5.8%, 3/52) in the full analysis set (P < 0.001).
A Dietary Supplement in the Management of Patients with Lumbar Osteochondrosis: A Randomized, Double-Blinded, Placebo-Controlled Study
Laky B et al. • Nutrients (2024)
In conclusion, this multi-nutrient supplement might not only stabilize the progression of lumbar osteochondrosis, but it might also potentially even increase IVD volumes as detected on MRIs.
- Despite no significance regarding the distribution of Pfirrmann grade changes (improvement, no change, worsening; p = 0.259), in the supplement group, one patient achieved a three-grade improvement, and worsening of Pfirrmann grades were only detected in the placebo group (9.1%).
- Disc degeneration according to Pfirrmann classifications remained stable during the 3-month intervention in both groups.
- Furthermore, in-depth evaluations of MRIs showed significantly higher 3D-measured volume changes (increase) in the supplement (+740.3 ± 796.1 mm3) compared to lower 3D-measured volume changes (decrease) in the placebo group (-417.2 ± 875.0 mm3; p < 0.001).
Metabolic plasticity of the gut microbiome in response to diets differing in glycemic load in a randomized, crossover, controlled feeding study
Hullar MA et al. • The American journal of clinical nutrition (2025)
In healthy humans, diet impacts microbial metabolism and enzymatic activity but not the overall diversity of the gut microbiome.
- Overall community structure measured by alpha and beta diversity was not significantly different across the diets, although diet did significantly increase the abundance of 13 of 161 genera (Padj < 0.05) and 5 species in the LGL diet and 7 species in the HGL diet.
- In healthy humans, diet impacts microbial metabolism and enzymatic activity but not the overall diversity of the gut microbiome.
- This emphasizes the relevance of dietary components in activating expression of specific bacterial genes and their impact on host metabolism.
A novel nutritional supplement containing amino acids and chromium decreases postprandial glucose response in a randomized, double-blind, placebo-controlled study
Östman E et al. • PloS one (2020)
Future studies should clarify, whether regular consumption of the supplement improves markers of disease or could play a role in a diet aiming at preventing the development of diabetes.
- In the intention-to-treat-analysis (n = 60) the supplement resulted in a decreased venous blood glucose iAUC0-120min compared to placebo, mean (SE) of 68.7 (6.6) versus 52.2 (6.8) respectively, a difference of -16.5 mmol/L•min (95% CI -3.1 to -30.0, p = 0.017).
- The Cmax for venous blood glucose for the supplement and placebo were 6.45 (0.12) versus 6.10 (<0.12), respectively, a difference of -0.35 mmol/L (95% CI -0.17 to -0.53, p<0.001).
- In the per protocol-analysis (n = 48), the supplement resulted in a decreased Cmax compared to placebo from 6.42 (0.14) to 6.12 (0.14), a difference of -0.29 mmol/L (95% CI -0.12 to -0.47, p = 0.002).
Dietary Intervention With a Targeted Micronutrient Formulation Reduces the Visual Discomfort Associated With Vitreous Degeneration
Ankamah E et al. • Translational vision science & technology (2021)
The findings of this study indicate improvements in vision-related quality of life and visual function of patients suffering from vitreous floaters after supplementation with a formulation of antioxidative and antiglycation micronutrients.
- After supplementation, the active group reported a significant decrease in their visual discomfort from floaters (P < 0.001), whereas the placebo group had no significant change in their visual discomfort (P = 0.416).
- At 6 months, there was a significant decrease in vitreous opacity areas in the active group (P < 0.001) and an insignificant increase in vitreous opacity areas in the placebo group (P = 0.081).
- Also, there was a significant improvement in photopic functional contrast sensitivity with positive contrast polarity in the active group after supplementation (P = 0.047).
Efficacy of a mouthwash containing ε-poly-L-lysine, funme peptides and domiphen in reducing halitosis and supragingival plaque: a randomized clinical trial
Shen S et al. • BMC oral health (2024)
The combination of ε-PL, FP and domiphen demonstrated potent inhibitory and bactericidal effects against the tested oral pathogens, and the newly formulated mouthwash added with the combination exhibited anti-dental plaque and anti-halitosis properties in a clinical trial and was safe.
- After 7 days, the VSC levels of the and control groups were reduced by 50.27% and 32.12%, respectively, and notably cutting severe halitosis by 57.03% in the test group.
- Additionally, the Plaque Index (PLI) of the test and control group decreased by 54.55% and 8.38%, respectively, and there was a significant difference in PLI between the two groups after 7 days (P < 0.01).
- The combination of ε-PL, FP and domiphen demonstrated potent inhibitory and bactericidal effects against the tested oral pathogens, and the newly formulated mouthwash added with the combination exhibited anti-dental plaque and anti-halitosis properties in a clinical trial and was safe.
Pilot study of the effects of lisdexamfetamine on cocaine use: A randomized, double-blind, placebo-controlled trial
Mooney ME et al. • Drug and alcohol dependence (2015)
LDX did not significantly reduce cocaine use compared to PBO in the randomized sample.
- Retention rates were higher though not significantly different in the PBO (71.4%) than the LDX condition (57.1%).
- Compared to those in the PBO condition, those receiving LDX were more likely to report experiencing (ps<0.05) diarrhea (45.5% vs. 14.3%), headaches (45.5% vs. 9.5%), and anxiety (31.8% vs. 4.8%).
- LDX did not significantly reduce cocaine use compared to PBO in the randomized sample.
L-lysine as an adjunct to risperidone in patients with chronic schizophrenia: a double-blind, placebo-controlled, randomized trial
Zeinoddini A et al. • Journal of psychiatric research (2014)
Iranian registry of clinical trials (www.irct.ir): IRCT201202201556N33.
- Clinical trial examining L-Lysine efficacy
- Published in Journal of psychiatric research (2014)
- Further research warranted to confirm findings
Short-Term Supplementation of Sodium Nitrate vs. Sodium Chloride Increases Homoarginine Synthesis in Young Men Independent of Exercise
Tsikas D et al. • International journal of molecular sciences (2022)
Plasma nitrite concentration turned out to be a more discriminant marker of NaNO3 ingestion than plasma nitrate (area under the receiver operating characteristic curve: 0.951 vs. 0.866, p < 0.0001 each).
- At the end of the study, the plasma concentrations of homoarginine (hArg; by 24%, p = 0.0001), citrulline and ornithine (Cit/Orn; by 16%, p = 0.015), and glutamine/glutamate (Gln/Glu; by 6%, p = 0.0003) were higher in the NaNO3 group compared to the NaCl group.
- The plasma concentrations of sarcosine (Sarc; by 28%, p < 0.0001), tyrosine (by 14%, p = 0.0051), phenylalanine (by 8%, p = 0.0026), and tryptophan (by 8%, p = 0.0047) were lower in the NaNO3 group compared to the NaCl group.
- The plasma Kgaa/KhArg ratio was lower in the NaNO3 group compared to the NaCl group (1.57 vs. 2.02, p = 0.0034).
Bioavailable Lysine Assessed Using the Indicator Amino Acid Oxidation Method in Healthy Young Males is High when Sorghum is Cooked by a Moist Cooking Method
Paoletti A et al. • The Journal of nutrition (2022)
Although the bioavailability of lysine in sorghum is high, its lysine content is limiting.
- The bioavailability of lysine from sorghum was 94%.
- Upon complementation with lentils, there was a decline in the oxidation of L-[1-13C] phenylalanine by 19% (P < 0.0495), reflecting an improvement in available lysine in the mixed meal due to increased lysine intake.
- Although the bioavailability of lysine in sorghum is high, its lysine content is limiting.
Steroids and L-Lysine Aescinate for Acute Radiculopathy Due to a Herniated Lumbar Disk
Oros M et al. • Medicina (Kaunas, Lithuania) (2019)
Among patients with acute radiculopathy due to a herniated lumbar disk a short course of IV dexamethasone or L-lysine aescinate resulted in pain improvement at 15th and 30th day.
- Among patients with acute radiculopathy due to a herniated lumbar disk a short course of IV dexamethasone or L-lysine aescinate resulted in pain improvement at 15th and 30th day.
- Dexamethasone may be preferable if a longer-term analgesic effect is needed.
- Taking into account side effects of dexamethasone, a solution of L-lysine aescinate can be used to relieve pain symptoms.
Supplementing a low-protein diet with dibasic amino acids increases urinary calcium excretion in young women
Bihuniak JD et al. • The Journal of nutrition (2014)
Larger and longer clinical trials are needed to clarify the possible benefit of arginine and lysine on calcium absorption.
- There was no difference in calcium absorption between the diet supplemented with CaSR-AAAs (22.9 ± 2.0%) and the control diet (22.3 ± 1.4%) (P = 0.64).
- However, calcium absorption tended to be greater during the DAA supplementation period (25.2 ± 1.4%) compared with the control diet period (22.3 ± 1.4%) (P < 0.10).
- Intestinal calcium absorption was measured between days 5 and 6 using dual-stable calcium isotopes ((42)Ca, (43)Ca, and (44)Ca).