Aggregated peptides lose bioavailability and may cause injection site reactions
Whelan SA, Dias WB, Thiruneelakantapillai L, Lane MD, Hart GW
The injections can only help aid any additional efforts you make to lose weight
B12 injections support metabolism and energy, which may complement weight management efforts when combined with appropriate diet and exercise
Since for most people it is impractical to take supplements several times a day, a single dosage of 250-500 micrograms seems to be the best solution
However, it has been classified as GRAS (Generally Recognized As Safe) as a food additive, and is commonly used in regenerative medicine under professional supervision