The well-known geriatrician-haematologist Larry Solomon, working at Yale University in the USA, wrote 20 years ago: if I had treated only those people who actually had too low serum B12 and elevated MMA values, then I would not have treated approximately two-thirds of the people with a favourable response to B12 supplementation (note: partly via injections, partly via oral supplementation)
The benefits of vitamin B12 can include improved red blood cell production, support for nerves and mood, and a smoother sense of focus that shows up in how you plan, prioritize, and follow through
Morning dosing is generally preferred to align with natural metabolic patterns, though this has not been rigorously studied
Skin, tendons, ligaments, and connective tissues all require constant collagen turnover