GLOSSARY

Hydroxocobalamin is a hydroxy cobalamin form used in some medical preparations, whose route and indication are part of its assessment.

Cobalamin names the B12 family. Methylcobalamin and adenosylcobalamin are coenzyme forms; cyano- and hydroxocobalamin can be converted. Active branding does not establish superiority for everyone. Route, amount and deficiency cause matter, and oral products and injectable medicines are not interchangeable solely because their names are related; clinical circumstances govern their use.

Food-bound B12 must first be released, then normally uses gastric intrinsic factor and absorption in the terminal small intestine. A small fraction can also enter by an independent pathway. Package amount is therefore not the absorbed amount, and gastric or ileal problems can impair status despite adequate food. These mechanisms help explain why dietary and medical correction strategies can differ.

B12 deficiency can affect blood formation and nerves without always causing overt anaemia. Serum B12, methylmalonic acid and sometimes homocysteine provide complementary information, but kidney function and other causes affect some markers. For a tired athlete, combined evidence is more informative than one result or a brief response to an energy drink, which does not establish correction of the underlying issue.