Why it is for you

This is for the person whose gut cannot get B12 out of food, whoever they are: anyone over fifty with a thinning stomach lining, anyone on long-term acid-lowering medicine or metformin, anyone eating no animal food, anyone after gut surgery, and anyone with an autoimmune attack on intrinsic factor. It is also for the root-cause picture where tiredness, numb feet and a foggy head arrive together, because one stalled enzyme explains all three. It pairs with folate and B6, since the three work the same methyl cycle and filling one alone can leave the picture half corrected, and with iron if that is short too. If you have numbness in the feet, this belongs in the plan before any metabolic work, because starved nerve is the tissue every later thing has to act through.