If you're feeling chronically fatigued, experiencing "pins and needles" in your hands and feet, or following a plant-based diet, a B12 supplement might be exactly what you need. Who Needs a B12 Supplement?

Your Essential Guide to Buying Vitamin B12 Supplements Vitamin B12, or cobalamin, is a powerhouse nutrient that keeps your nerves firing, your red blood cells healthy, and your DNA stable. Because our bodies don't produce it, we must get it from animal products or supplements.

Most healthy adults need about . While many get this from meat, eggs, and dairy, several groups are at higher risk for deficiency: Vitamin B12: MedlinePlus Medical Encyclopedia