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Head-to-head evidence comparison — which supplement is right for you?
B-Complex wins 1 of 3 categories. Both are solid choices — the best pick depends on your specific goals.
Verdict
Probably helps
5 of 8 studies with measurable effects showed benefit.
Top outcomes
Verdict
Likely helps
6 of 6 studies with measurable effects showed benefit.
Top outcomes
1 capsule daily (per label)
Morning with breakfast
Methylated B-complex (methylcobalamin, methylfolate)
10-15g
Any time of day, With vitamin C for enhanced synthesis
Hydrolyzed collagen peptides (powder)
2-4 weeks
4-8 weeks
Immediate
8-12 weeks
8-12 weeks
12 weeks
First week
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.
A Comparative Study Evaluating the Effectiveness of Folate-Based B Vitamin Intervention on Cognitive Function of Older Adults under Mandatory Folic Acid Fortification Policy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials
Nutrients (2024) · Meta analysis · n=42768
The meta-analysis on the effects of folate-based B vitamin supplementation on cognitive function showed a significant overall impact (Z = 3.84; p = 0.0001; SMD, 0.18; 95% CI, 0.09, 0.28).
A Systematic Review and Meta-Analysis of B Vitamin Supplementation on Depressive Symptoms, Anxiety, and Stress: Effects on Healthy and 'At-Risk' Individuals
Nutrients (2019) · Meta analysis · n=2015
Regarding individual facets of mood, B vitamin supplementation benefited stress (n = 958, SMD = 0.23, 95% CI = 0.02, 0.45, p = 0.03).
Effects of Collagen Supplements on Skin Aging: A Systematic Review and Meta-Analysis
The American Journal of Medicine (2025) · Meta analysis · n=1474
23 RCTs with 1474 participants
Effect of collagen supplementation on knee osteoarthritis: an updated systematic review and meta-analysis of randomised controlled trials
Clinical and experimental rheumatology (2025) · Meta analysis · n=870
The meta-analysis revealed an overall significant improvement of both function [MD, -6.46 (95% CI -9.52, -3.40); I2=75%; p=0.00001] and pain scores [MD, -13.63 (95% CI -20.67, -6.58); I2=88%; p=0.00001], favouring collagen supplementation.
Impact of Collagen Peptide Supplementation in Combination with Long-Term Physical Training on Strength, Musculotendinous Remodeling, Functional Recovery, and Body Composition in Healthy Adults: A Systematic Review with Meta-analysis
Sports medicine (Auckland, N.Z.) (2024) · Meta analysis · n=768
This systematic review and meta-analysis represents the first comprehensive investigation into the effects of long-term CP supplementation combined with regular physical training on various aspects of musculoskeletal health in adults.
Multiple meta-analyses show small but statistically significant benefits for cognitive function in older adults and stroke prevention populations. Effect sizes are modest (SMD ~0.15-0.18). Benefits may be more pronounced in B-vitamin deficient populations.
Meta-analysis of 23 RCTs (n=1474) showed high-quality studies had less effect than industry-funded studies. Benefits include improved skin elasticity and hydration. Hydrolyzed collagen peptides preferred for bioavailability.
AI-estimated from published studies. Interpret as directional guidance.
B-Complex has a higher evidence score (9/10 vs 9/10) and wins in 1 of 3 categories.
For prenatal support, B-Complex has a higher relevance score (90 vs 65).
No known interactions between B-Complex and Collagen have been documented in our database. However, always consult a healthcare provider before combining supplements.