B12 & cognition review — ScienceDirect (2025). [Narrative review]. https://www.sciencedirect.com/science/article/pii/S266645932500040X
Cureus - Neurological Sequelae SR (2025). [Systematic Review]. https://pmc.ncbi.nlm.nih.gov/articles/PMC12143585/
Habtie TE et al. – Oxidative medicine and cellular longevity (2025). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/40458194/
Ulloque-Badaracco JR et al. – Frontiers in public health (2025). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/39991695/
Castillo LF et al. – Annual review of nutrition (2025). [Review]. https://pubmed.ncbi.nlm.nih.gov/40315282/
Janko RK et al. – American journal of health promotion : AJHP (2025). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/39136672/
Verduci E et al. – Journal of pediatric gastroenterology and nutrition (2025). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/40819279/
Deng XL et al. – Frontiers in endocrinology (2025). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/40612436/
Niklewicz et al. — meta-analysis (2024). [SR + meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/39373282/
Vegan B12 scoping review (2024). [Scoping review]. https://pmc.ncbi.nlm.nih.gov/articles/PMC11124153/
Sandoval Leiva T et al. – Nutricion hospitalaria (2024). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/38896115/
Abdelwahab OA et al. – Irish journal of medical science (2024). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/38231320/
Desmond MA et al. – Nutrients (2024). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/38474851/
Zhang N et al. – Clinical nutrition (Edinburgh, Scotland) (2024). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/38824900/
Bekdash RA – International journal of molecular sciences (2024). [Review]. https://pubmed.ncbi.nlm.nih.gov/38612845/
German cross-sectional — Annals of Medicine (2023). [Cross-sectional]. https://www.tandfonline.com/doi/full/10.1080/07853890.2023.2269969
Alruwaili M et al. - Healthcare (2023). [Systematic Review & Meta-Analysis]. https://pubmed.ncbi.nlm.nih.gov/37046885/
Jensen CF – Nutrition reviews (2023). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/36413044/
Neufingerl N et al. – Nutrients (2023). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/37892416/
Manapurath R et al. – The Journal of nutrition (2023). [RCT]. https://pubmed.ncbi.nlm.nih.gov/36889645/
Fardous AM et al. – Nutrients (2023). [Review]. https://pubmed.ncbi.nlm.nih.gov/37960352/
Heilfort L et al. – Nutrition and cancer (2023). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/35819060/
Modica JS et al. – Journal of the neurological sciences (2023). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/37210937/
Clements M et al. – Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research (2022). [RCT]. https://pubmed.ncbi.nlm.nih.gov/36128889/
McMullin PR et al. – Current pain and headache reports (2022). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/35794449/
Rogers et al. — meta-analysis (2021). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/33809274/
Nalder et al. — Nutrients (2021). [Systematic review & MA]. https://pubmed.ncbi.nlm.nih.gov/34371786/
Rashid S et al. – European journal of haematology (2021). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/33341967/
Anamnart C et al. – Journal of clinical neuroscience : official journal of the Neurosurgical Society of Australasia (2021). [RCT]. https://pubmed.ncbi.nlm.nih.gov/33992189/
Neufingerl N et al. – Nutrients (2021). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/35010904/
Karcz K et al. – Critical reviews in food science and nutrition (2021). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/32319307/
Stein J et al. – European journal of neurology (2021). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/33619867/
Sawangjit R et al. – Journal of alternative and complementary medicine (New York, N.Y.) (2020). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/32716261/
Li X et al. – International journal of medical sciences (2020). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/32218697/
Julian T et al. – Nutrients (2020). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/32722436/
Obeid et al. — Clin Chem Lab Med (2019). [Review]. https://pubmed.ncbi.nlm.nih.gov/31188752/
Ma F et al. – Current Alzheimer research (2019). [RCT]. https://pubmed.ncbi.nlm.nih.gov/31345146/
Naik S et al. – Nutrients (2019). [RCT]. https://pubmed.ncbi.nlm.nih.gov/31590426/
Sanderson SM et al. – Nature reviews. Cancer (2019). [Review]. https://pubmed.ncbi.nlm.nih.gov/31515518/
Yang W et al. – Journal of diabetes (2019). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/30615306/
Obeid R et al. — Nutrients (2019). [Review]. https://pubmed.ncbi.nlm.nih.gov/30791639/
Molloy AM - Annals of NY Academy of Sciences (2018). [Review]. https://pubmed.ncbi.nlm.nih.gov/29377209/
Langan & Goodbred — Am Fam Physician (2017). [Clinical review]. https://pubmed.ncbi.nlm.nih.gov/28925645/
Green R et al. - Nature Reviews Disease Primers (2017). [Comprehensive Review]. https://pubmed.ncbi.nlm.nih.gov/28660890/
Zhang DM et al. – Journal of geriatric psychiatry and neurology (2017). [Meta-analysis]. https://pubmed.ncbi.nlm.nih.gov/28248558/
Green R et al. — Nat Rev Dis Primers (2017). [Seminal review]. https://pubmed.ncbi.nlm.nih.gov/28660890/
Langan RC & Goodbred AJ — Am Fam Physician (2017). [Clinical review]. https://pubmed.ncbi.nlm.nih.gov/28925645/
Coppedè F – Archives of toxicology (2016). [Review]. https://pubmed.ncbi.nlm.nih.gov/27600794/
Rizzo G et al. — Nutrients (2016). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/27886044/
Dangour AD et al. - American Journal of Clinical Nutrition (OPEN Trial) (2015). [RCT]. https://pubmed.ncbi.nlm.nih.gov/26135351/
Pawlak et al. — Eur J Clin Nutr (2014). [Systematic review]. https://pubmed.ncbi.nlm.nih.gov/24667752/
Scaglione F et al. – Xenobiotica; the fate of foreign compounds in biological systems (2014). [Review]. https://pubmed.ncbi.nlm.nih.gov/24494987/
Stabler SP - New England Journal of Medicine (2013). [Clinical Review]. https://pubmed.ncbi.nlm.nih.gov/23301732/
Pietrzik K et al. – Clinical pharmacokinetics (2010). [Review]. https://pubmed.ncbi.nlm.nih.gov/20608755/
Tucker KL et al. - American Journal of Clinical Nutrition (Framingham) (2000). [Cohort Study]. https://pubmed.ncbi.nlm.nih.gov/10648266/
Lewis DP et al. – The Annals of pharmacotherapy (1995). [Review]. https://pubmed.ncbi.nlm.nih.gov/8520091/
B12 absorption mechanism — established (Established). [Established science].