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Head-to-head evidence comparison — which supplement is right for you?
Arginine wins 1 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Probably helps
11 of 19 studies with measurable effects showed benefit.
Top outcomes
Verdict
Probably helps
8 of 15 studies with measurable effects showed benefit.
Top outcomes
3-6g daily
30-60 minutes before exercise, Divided doses throughout the day for cardiovascular benefits
L-Arginine powder or capsules
500-2000mg daily for lipid effects; 50-500mg for general health
With food (reduces flush), Evening for lipid effects, Split doses for high amounts
Immediate-release niacin (nicotinic acid)
30-60 minutes
During exercise
2-4 weeks
Immediate
4-8 weeks
4-8 weeks
30-60 minutes after dose
Nutritional interventions for preventing and treating pressure ulcers
The Cochrane database of systematic reviews (2024) · Meta analysis · n=7920
Compared to standard diet, protein supplements may result in little to no difference in pressure ulcer incidence (protein 21 per 1000, standard diet 28 per 1000; RR 0.75, 95% CI 0.49 to 1.14; 4 studies, 4264 participants; low-certainty evidence).
Comparative Effects of Different Nutritional Supplements on Inflammation, Nutritional Status, and Clinical Outcomes in Colorectal Cancer Patients: A Systematic Review and Network Meta-Analysis
Nutrients (2023) · Meta analysis · n=2841
Glutamine was superior in decreasing tumor necrosis factor-α (MD -25.2; 95% CrI [-32.62, -17.95]), whereas combined omega-3 and arginine supplementation was more effective in decreasing interleukin-6 (MD -61.41; 95% CrI [-97.85, -24.85]).
Nutritional interventions for treating foot ulcers in people with diabetes
The Cochrane database of systematic reviews (2020) · Meta analysis · n=629
It is also uncertain whether arginine, glutamine and β-hydroxy-β-methylbutyrate supplement increases the proportion of ulcers healed at 16 weeks compared with placebo (RR 1.09, 95% CI 0.85 to 1.40).
Niacin for primary and secondary prevention of cardiovascular events
The Cochrane database of systematic reviews (2017) · Meta analysis · n=39195
Participants randomised to niacin were more likely to discontinue treatment due to side effects than participants randomised to control group (RR 2.17, 95% CI 1.70 to 2.77; participants = 33,539; studies = 17; I2 = 77%; moderate-quality evidence).
Effect of lipid-lowering therapies on lipoprotein(a) levels: a comprehensive meta-analysis of randomized controlled trials
Atherosclerosis (2025) · Meta analysis · n=145314
Among available LLTs, PCSK9mAbs, inclisiran, CETPi, and niacin significantly decreased Lp(a) levels.
A terminal metabolite of niacin promotes vascular inflammation and contributes to cardiovascular disease risk
Nature medicine (2024) · Meta analysis
Lastly, treatment with physiological levels of 4PY, but not its structural isomer 2PY, induced expression of VCAM-1 and leukocyte adherence to vascular endothelium in mice.
Based on meta-analysis showing mean reductions of 5.39 mmHg systolic and 2.66 mmHg diastolic. Effects are modest and may not be clinically significant for all individuals. GI side effects increase notably above 6g.
Based on multiple meta-analyses showing HDL increases. Higher doses increase discontinuation rates due to side effects (RR 2.17). Immediate-release forms have better lipid effects but more flushing.
AI-estimated from published studies. Interpret as directional guidance.
Arginine has a higher evidence score (9/10 vs 9/10) and wins in 1 of 3 categories.
For reduce inflammation, Niacin has a higher relevance score (85 vs 70).
No known interactions between Arginine and Niacin have been documented in our database. However, always consult a healthcare provider before combining supplements.