Tingling, numbness and balance problems: could it be B12?

Why low B12 affects nerves

B12 is needed to maintain myelin, the fatty coating that insulates nerve fibers and lets signals travel quickly. When B12 runs low for months or years, myelin and the nerve fibers themselves can be damaged. The longest nerves, which run to the feet, and the spinal cord pathways that carry position sense tend to be affected first.

Because the body stores several years' worth of B12, symptoms often creep in slowly. The NIH Office of Dietary Supplements notes that deficiency can take years to appear and that numbness and tingling can occur even without anemia.

Symptoms to notice

MedlinePlus lists a broad range of nervous system effects from long-term B12 deficiency. Some are physical, others affect thinking and mood, which is why the condition is sometimes mistaken for stress, aging or early dementia.

• Pins and needles or numbness in both feet, later the hands
• Unsteadiness, especially in the dark or with your eyes closed
• Weakness, stiffness or a change in the way you walk
• Memory problems, slowed thinking or confusion
• Low mood, irritability and, rarely, psychiatric symptoms
• Vision changes from optic nerve involvement, which is uncommon

Why timing matters

Many people see their nerve symptoms improve with treatment, although recovery can take months. Damage that has been present a long time may only partly improve. MedlinePlus states that nerve damage can be permanent if treatment does not start within 6 months of symptoms.

That is why nerve symptoms change the urgency. If you have new tingling, numbness or balance problems and a risk factor for low B12, testing should happen soon rather than waiting for your next annual checkup.

Who is at higher risk

• Adults over 60, partly because atrophic gastritis becomes more common with age
• People with pernicious anemia or other autoimmune conditions such as thyroid disease or type 1 diabetes
• Anyone who has had gastric bypass or surgery on the stomach or lower small intestine
• Long-term users of metformin or acid-reducing medicines
• Vegans and strict vegetarians who do not supplement
• People who use recreational nitrous oxide, which inactivates B12
• People taking high-dose folic acid with low B12, a pairing the ODS links to worse cognitive outcomes

What gets tested

A serum B12 level is the starting point, but a 'low-normal' value does not rule out deficiency when nerve symptoms are present. The ODS describes methylmalonic acid (MMA) as the most sensitive marker and suggests checking it when B12 is in the borderline zone. Homocysteine can help too, though it is less specific.

Your clinician will usually add a complete blood count, folate, glucose or A1c, thyroid tests and kidney function. If pernicious anemia is suspected, antibodies against intrinsic factor can confirm it. Blood should be drawn before the first injection, since a dose raises levels within days and can hide the original deficiency.

When it is not B12

The National Institute of Neurological Disorders and Stroke names diabetes as the leading cause of peripheral neuropathy in the U.S. Alcohol, kidney and liver disease, thyroid and other hormone problems, autoimmune disease, some infections, chemotherapy, nerve compression and certain medicines can all cause similar symptoms. Interestingly, too much vitamin B6 from supplements can also cause neuropathy.

Some patterns need a neurologist or urgent care rather than a telehealth visit. Seek prompt in-person care if you have any of the following.

• Weakness that is getting worse over days or weeks
• Symptoms on only one side of the body or in one limb
• New loss of bladder or bowel control
• Rapidly spreading numbness, or numbness around the groin or buttocks
• Sudden confusion, trouble speaking or facial drooping (call 911)

What recovery looks like

Treatment usually starts with a series of injections given closely together to rebuild stores, followed by a maintenance schedule set by your clinician. Blood levels respond quickly, but nerves heal on their own timeline. Some people notice steadier balance or less tingling within weeks; for others, improvement continues gradually over many months.

Keep a simple symptom diary so you and your clinician can compare how you feel over time. If symptoms are not improving, or are getting worse, that is a signal to reassess the diagnosis rather than simply continue injections.

How HealifyMD can help

Your clinician reviews your symptoms, medicines, diet and history, orders the right labs (priced separately), and explains what the results mean. If you are deficient and injections are the right route, B12 Injection costs from $125/month with no membership fee, confirmed at the eligibility review. Follow-up labs and symptom check-ins show whether the plan is working. If your pattern points elsewhere, your clinician will help you get the right in-person care.