anemia might be treated with vitamin b12 injections Do You Need a Prescription for Injections? Vitamin B12 Injection - We
Description
112 A meta-analysis of observational studies (n = 21 837 people 1290 years old) revealed a significant inverse association between dietary intake of vitamin B 12 and/or vitamin B 12 supplementation and the risk of depression in women

Prevalence of Micronutrient Deficiencies Prior to Bariatric Surgery: Tehran Obesity Treatment Study (TOTS) Obes

PMID 18644225

This is especially true if you have done more than 3 injections and still find the b12 shots not working
