Vitamin B12 is essential for your body's energy production, nerve function, and red blood cell formation. Unfortunately, many people don't realize that they may be lacking this crucial vitamin. If you're experiencing High Vitamin B12 Levels: Causes, Symptoms, Treatment & More PharmEasy B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics Signs You May Have a B12 Deficiency If you've been feeling weak, foggy, or experiencing numbness in your hands and feet, it could be a sign of vitamin B12 deficiency. B12 is essential for nerve function and red blood