1. Numbness, tingling, or “pins and needles”
Persistent tingling or numbness—especially in the hands or feet—can occur when B12 deficiency affects peripheral nerves.
2. Problems with balance or walking
B12 deficiency can affect coordination and the nervous system, causing unsteadiness, difficulty walking, or falls.
3. Memory, concentration, or thinking changes
Some people develop difficulty concentrating, memory problems, confusion, or other cognitive changes. Depression and anxiety can also occur.
4. Severe or persistent fatigue and weakness
B12 is needed to produce healthy red blood cells. Deficiency can cause anemia, resulting in extreme tiredness, weakness, shortness of breath, dizziness, or headaches.
Other clues
A sore or unusually red tongue, mouth ulcers, vision problems, or unexplained changes in mood can also occur.
What should you do?
Don’t assume these symptoms automatically mean you need B12. They can have many other causes. A healthcare professional can evaluate your symptoms and use blood testing to investigate B12 deficiency and its underlying cause.
This is particularly important if you have risk factors such as a diet very low in B12, problems absorbing nutrients, certain stomach or intestinal conditions, or use medicines such as metformin or proton-pump inhibitors.
Don’t delay evaluation when neurological symptoms are present. B12-related nerve damage can sometimes become irreversible if the deficiency goes untreated.
And avoid taking large doses of B12 simply because you have one of these symptoms—the right approach is to identify whether you actually have a deficiency and why.
