Vitamin B12 deficiency is pretty common, and many people take B12 injections
It depends on the cause
Tracking body measurements, progress photos, and how your clothes fit provides a more accurate picture of fat loss than relying on the scale alone
Doses of vitamin B12 exceeding 10 mcg daily may produce a hematologic response in patients who have a folate deficiency

Examples include: Wound repair models that require fibroblast migration, extracellular matrix deposition, and remodeling Tendon/ligament repair models focused on cell survival, growth and restoration of tissue organization[1] Research in fibrosis and remodeling where thymosin beta-4 related pathways are of interest[2] Studies associated with angiogenesis (e.g., when vascular support is a limiting factor in tissue regeneration) [5] Since synergy is an outcome claim that must be demonstrated experimentally, it is hypothesized here: if BPC-157 and TB-500 affect different critical points of repair (e.g., gene expression versus cytoskeleton mobilization), combined administration in preclinical designs could produce additive or multiplicative improvements in migration rate, wound closure, tissue organization, or histological markers of remodeling, depending on the model and evaluation criteria