看看這篇

https://www.justvitamins.co.uk/blog/cyanocobalamin-versus-methylcobalamin/#:~:text=There%20are%20two%20forms%20of,is%20therefore%20obviously%20naturally%20occuring.

能知道常見兩種型式的B12各有其效果，應該按每個人的狀況、需求來選擇。

要是搞不清楚自己確實需要什麽，可考慮複合型，如這種

https://www.amazon.com/NOW-B-12-2000-mcg-Lozenges/dp/B001QNPWGM

劑量有點大，適合血B12低時快速補充。一周後改為隔日一片。