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Head-to-head evidence comparison — which supplement is right for you?
L-Glutamine and Vitamin B6 are closely matched across evidence, studies, and safety.
Verdict
Likely helps
3 of 3 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
9 of 11 studies with measurable effects showed benefit.
Top outcomes
Shared outcomes (1)
Outcomes where both L-Glutamine and Vitamin B6 have evidence — compare verdict strength side-by-side.
5-10g
Post-workout, Before bed, Or split throughout day
L-Glutamine powder
25-100mg daily
Morning with food, Can take with other B vitamins
P-5-P (Pyridoxal-5-Phosphate)
2-4 weeks
2-4 weeks
1-2 weeks
2-4 weeks
1-2 cycles
Months of high doses
A Phase 3 Trial of l-Glutamine in Sickle Cell Disease
The New England journal of medicine (2018) · Rct · n=230
A total of 230 patients (age range, 5 to 58 years; 53.9% female) were randomly assigned, in a 2:1 ratio, to receive l-glutamine (152 patients) or placebo (78 patients).
What Is the Role of Nutritional Supplements in Support of Total Hip Replacement and Total Knee Replacement Surgeries? A Systematic Review
Nutrients (2018) · Systematic review
Amino acid supplementation is reported to reduce muscle atrophy and accelerate return of functional mobility.
Evidence and gaps in clinical outcomes of novel pharmacologic therapies for sickle cell disease: A systematic literature review highlighting insights from clinical trials and real-world studies
Blood reviews (2025) · Systematic review · n=97
A pivotal phase III study of l-glutamine showed that patients treated with l-glutamine had a 25 % reduction in pain crises and 33 % fewer hospital days compared to placebo. l-glutamine was generally well tolerated with minimal side effects.
Dosage exploration of combined B-vitamin supplementation in stroke prevention: a meta-analysis and systematic review
The American journal of clinical nutrition (2024) · Meta analysis · n=76664
In areas without and with partial folic acid fortification, combined B-vitamin supplementation significantly reduced the risk of stroke by 34% [RR: 0.66; 95% confidence interval (CI): 0.50, 0.86] and 11% (RR: 0.89; 95% CI: 0.79, 1.00), respectively.
Vitamin and mineral supplementation for maintaining cognitive function in cognitively healthy people in mid and late life
The Cochrane database of systematic reviews (2018) · Meta analysis · n=83000
We found that giving B vitamin supplements to cognitively healthy adults, mainly in their 60s and 70s, probably has little or no effect on global cognitive function at any time point up to 5 years (SMD values from -0.03 to 0.06) and may also have no effect at 5-10 years (SMD -0.01).
Drug Efficacy in the Treatment of Antipsychotic-Induced Akathisia: A Systematic Review and Network Meta-Analysis
JAMA network open (2024) · Meta analysis · n=492
No association between effect sizes and psychotic severity was found.
Based on RCT showing reduced URTI incidence in combat athletes (n=21) and enhanced IgA levels. Limited sample size and specific population studied. Effect may be primarily in high-stress/training conditions.
Based on systematic review of nutritional interventions for PMS psychological symptoms. Evidence quality limited by study heterogeneity and need for more consistent protocols.
AI-estimated from published studies. Interpret as directional guidance.
Both L-Glutamine and Vitamin B6 are closely matched — the best choice depends on your specific health goals.
For support immune system, L-Glutamine has a higher relevance score (70 vs 65).
No known interactions between L-Glutamine and Vitamin B6 have been documented in our database. However, always consult a healthcare provider before combining supplements.