Foods high in B12 include fish, meat, poultry, eggs, dairy produce, and foods that are fortified with B12 (like some breakfast cereals.) If you follow a restrictive diet or have a condition that impacts absorption, you could be at risk for a B12 deficiency
I wouldn't turn to anyone else in the world
Serum B12 reference ranges vary between laboratories, but generally, levels below 148 pmol/L are considered deficient, whilst levels between 148258 pmol/L are regarded as borderline and may warrant further investigation or a trial of treatment, particularly if symptoms are present

3 BDNF Hippocampus mRNA Increase in BDNF exon III mRNA in the hippocampus after a single dose (Dolotov et al., 2006) 7 AA Heptapeptide Met-Glu-His-Phe-Pro-Gly-Pro sequence ACTH(4-10) + stabilizing tripeptide Pro-Gly-Pro 813.93 Da Molecular Weight Formula CHNOS CAS 80714-61-0 | Purity 98% HPLC DA/5-HT Neurotransmitters Activation of the brain's dopaminergic and serotonergic systems (Eremin et al., 2005) Russia 2011 Approved List of Vital and Essential Medicines of the Russian Federation (Stroke, cognition) Mechanism of Action Neurotrophin & Neuroprotection Upregulation of BDNF/trkB, dopaminergic/serotonergic activation and anti-ischemic neuroprotection Primary Route BDNF/trkB Upregulation of Neurotrophic Factor Semax rapidly increases BDNF levels (1.4x protein, 3x exon III mRNA) and phosphorylation of its receptor trkB (1.6x) in the hippocampus after a single administration of 50 g/kg