Battle tiredness and fatigue with these vitamin B12 supplements. There’s nothing worse than feeling tired and listless, especially when you’ve already been trying to tackle the problem by making sure you’ve been getting enough good-quality sleep a night. Sometimes it’s not just your life choices making you tired, your fatigue could have more to do with the foods (or lack of) that you’re putting in your body. One of the most important vitamins for a normal and healthy energy-yielding metabolism is vitamin B12. Also known as cyanocobalamin, this vitamin is also essential for psychological function, maintaining a healthy nervous system and reducing tiredness and fatigue.