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Head-to-head evidence comparison — which supplement is right for you?
Pine Bark Extract and Vitamin A are closely matched across evidence, studies, and safety.
Verdict
Likely helps
11 of 14 studies with measurable effects showed benefit.
Top outcomes
Verdict
Mixed evidence
8 of 17 studies with measurable effects showed benefit.
Top outcomes
100-200mg daily
Morning with food, Can be divided into two doses
Pycnogenol (standardized extract)
2500-5000 IU daily (retinol); up to 25000 IU (beta-carotene)
With fat-containing meal, Any time of day
Mixed carotenoids or low-dose retinyl palmitate
4-8 weeks
6-12 weeks
4-8 weeks
Initial use
2-4 weeks
2-4 weeks
4-8 weeks
With chronic excess
Phlebotonics for venous insufficiency
The Cochrane database of systematic reviews (2020) · Meta analysis · n=7690
Pooled data suggest that phlebotonics probably increase adverse events slightly, compared to placebo (RR 1.14, 95% CI 1.02 to 1.27; 37 studies; 5789 participants; moderate-certainty evidence).
Pine bark (Pinus spp.) extract for treating chronic disorders
The Cochrane database of systematic reviews (2020) · Meta analysis · n=1641
In a mixed group of participants with type 1 and type 2 DM we do not know whether pine bark extract decreases HbA1c (MD -0.20 %, 95% CI -1.83 to 1.43; one study; 67 participants; very low-certainty evidence).
Effect of pycnogenol supplementation on blood pressure: A systematic review and meta-analysis of clinical trials
Phytotherapy research : PTR (2020) · Meta analysis · n=922
Pooled analysis suggested that pycnogenol supplementation can reduced systolic blood pressure (SBP) of (-3.22 mmHg; 95% CI [-5.52, -0.92]) and diastolic blood pressure (DBP; -1.91 mmHg; 95% CI [-3.64, -0.18]).
Effects of primary or secondary prevention with vitamin A supplementation on clinically important outcomes: a systematic review of randomised clinical trials with meta-analysis and trial sequential analysis
BMJ open (2024) · Meta analysis · n=672
Vitamin A did not reduce mortality in individually randomised trials (RR 0.99, 95% CI 0.93 to 1.05; I²=32%; p=0.19; 105 trials; moderate certainty), and this effect was not affected by the risk of bias.
Vitamin and Mineral Supplementation During Pregnancy on Maternal, Birth, Child Health and Development Outcomes in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis
Nutrients (2020) · Meta analysis · n=451723
IFA supplementation showed notable improvement in maternal anemia and the reduction in low birthweight, whereas LNS supplementation had no apparent effect on outcomes; further research that compares LNS and MMN supplementation could help understand differences with these commodities.
Vitamin A supplements for reducing mother-to-child HIV transmission
The Cochrane database of systematic reviews (2017) · Meta analysis · n=6601
Antepartum or postpartum vitamin A supplementation, or both, probably has little or no effect on mother-to-child transmission of HIV in women living with HIV infection and not on antiretroviral drugs.
Based on meta-analyses showing modest reductions in systolic (-3.22 mmHg) and diastolic (-1.91 mmHg) blood pressure. Effects are clinically small and studies show heterogeneity.
AI-estimated from published studies. Interpret as directional guidance.
Both Pine Bark Extract and Vitamin A are closely matched — the best choice depends on your specific health goals.
For healthy aging, Vitamin A has a higher relevance score (80 vs 70).
No known interactions between Pine Bark Extract and Vitamin A have been documented in our database. However, always consult a healthcare provider before combining supplements.