Your body needs vitamin B12 to keep blood cells healthy and to make your nerves work right. Here are some signs that you're low on this vitamin: https: wb.md 44GSGRp Vitamin B12 plays a role in far more than energy. When levels drop, the effects can be felt across multiple body systems, from fatigue, low mood and poor sleep, to appetite changes The Best and Worst Forms of Vitamin B12 Your body needs vitamin B12 to keep blood cells healthy and to make your nerves work right. Here are some signs that you're low on this vitamin: https: wb.md 44GSGRp Buy B12 Injections Vitamin B12 Injections at Home The truth about vitamin B12 and insomnia H.W. Woods