Vitamin B12 is important for the health of your nervous system and your red blood cells. It can be found in many animal products and fortified foods. In the United States, about 6% of people under age ...

This article was reviewed by Lynn Marie Morski, MD, JD. There’s not much research on B12 shots for weight loss. People with obesity tend to have lower vitamin B12 levels, but it’s unclear if B12 shots ...