B12 testing: should I be tested?

Vitamin B12 deficiency

Vitamin B12 helps make healthy blood cells. It also keeps your nerves working well. Low B12 is common and often missed. It can cause tiredness, tingling, memory problems, or trouble with balance. Testing makes sense if you have one of these symptoms. It also helps if you have a reason to be at risk. Risk factors include a vegan or mostly plant-based diet. They also include long-term use of certain stomach medicines or metformin. Past stomach or bowel surgery is another risk factor, as is another autoimmune condition like celiac disease. If your first B12 result is unclear, a second blood test can help. If deficiency is confirmed, more testing can find the cause. New numbness, tingling, or balance problems should be checked promptly, since nerve damage is not always fully reversible.