b12 is still low with injections Shots: Vitamin B12 Benefits, Uses, Risks Do B12 Injections Help with
Description
But how is this process made possible

Endocrine Journal , 59(7), 529538

Most of the time, the deficiency is related to the digestive system
Can birth control lead to vitamin deficiencies

Our study extends the findings of previous investigations demonstrating age-related impairment of NVC responses in older adults evoked and assessed by other methodologies including fMRI, fNIRS, and dynamic retinal vessel analysis [48,49,50,51]