can too many b12 injections be harmful You Get Much Vitamin B12? What You Need to Know

Many of the people surveyed would prefer their injections to be overseen by a doctor but felt they had no choice but to self-medicate more frequently to improve their quality of life

In contrast, synthetic B12 (cyanocobalamin) needs to be converted into its active form by your body before it can be used effectively

Eur J Clin Nutr 2006;60:791801

Intrinsic factor is efficient at absorbing a high percentage of a small dose of B12, but it becomes saturated after a meal containing an above-average amount of B12, and about 4 to 6 hours are required before it can efficiently absorb another dose (Institute of Medicine, 1998)