B12 shots can make people feel like they're "born again" by boosting mood, energy, memory and much more - especially in those who are deficient.
 
B12 is a nutrient needed to form red blood cells, DNA, and brain and nerve cells and thus, Vitamin B12 shots can help with energy levels, brain function, boosting mood, improving metabolism, and weight loss.
 
People often feel better within hours after their first injection.