What are Vitamin B12 injections Vitamin B12 injections are used to quickly raise your B12 levels when they're low or when your body can't absorb it properly from food or tablets. What Does B12 Help You Lose Weight? Kansas City Med Spa What You Need to Know About Vitamin B12 Duane NP Main benefits of B12 injections 1) Increased energy & reduced fatigue B12 helps convert food into usable energy Deficiency often causes tiredness, weakness, and low stamina 2) Healthy red blood cells Prevents Benefits of B12 Injections for Optimal Health