Why your feet burn at night, how to check if B12 is behind it, and what actually helps.
If your feet burn, tingle, or go numb at night, vitamin B12 deficiency deserves a place on your shortlist of causes. It is one of the most common nutritional causes of peripheral neuropathy, yet it is frequently missed — partly because the standard blood test can come back "normal" even while your nerves are already struggling. The good news: caught early, B12-related burning feet usually improve quickly once your levels are restored.
Vitamin B12 (cobalamin) is essential for two jobs your nervous system depends on: building myelin and keeping nerve cells healthy. Myelin is the fatty sheath that wraps nerve fibres the way insulation wraps an electrical wire — it lets signals travel fast and cleanly from your spinal cord down to your toes. When B12 runs low, the body can no longer maintain this sheath properly, and the myelin starts to break down in a process called demyelination.
Demyelination is not random. It hits the longest nerve fibres first, producing what neurologists call a dying-back (length-dependent) neuropathy: the parts of the nerve farthest from the spinal cord — the toes and feet — are affected before the hands, and the hands before anything higher up. Damaged and poorly insulated fibres misfire, which your brain reads as:
As the damage progresses, the same nerves lose their ability to carry sensation, so you may also notice reduced vibration sense, clumsiness, an unsteady gait, and eventually weakness or muscle wasting in the lower legs. Because severe or long-standing nerve damage can become permanent, early recognition genuinely matters.
B12 deficiency is common, but certain groups are at much higher risk:
If you fit any of these categories and your feet burn, do not dismiss it as "just getting older."
Burning feet are rarely the only clue. In many people, the earliest signs of B12 deficiency also include:
Because these overlap with many other conditions, the combination of burning feet plus any of the above should push you toward a blood test rather than self-treatment.
The standard first test is serum B12. Typical reference ranges sit around 200–900 pg/mL, with many labs flagging anything below roughly 200–300 as deficient. The catch: serum B12 measures what is circulating in your blood, not what your cells can actually use. It is possible — and not rare — to have genuine, symptom-causing B12 deficiency with a result inside the normal range.
Practical takeaway: if you have burning feet and a low-normal or borderline B12 result, ask your doctor about MMA and homocysteine before accepting a "you're fine." Check folate at the same time, because B12 and folate deficiency often travel together.
Intramuscular hydroxocobalamin is the standard treatment in most countries. A typical course is 1 mg every other day for two weeks, then maintenance doses. For pernicious anaemia and other absorption-blocking causes, injections continue for life — usually every 2–3 months.
Oral cyanocobalamin at 1000–2000 mcg daily works for many people, including some with mild absorption problems, because a small fraction (around 1%) is absorbed passively, without needing intrinsic factor or stomach acid. It is a reasonable option for dietary deficiency and for people who prefer to avoid injections — but the decision should be made with your doctor, not by guessing.
Blood counts typically normalise within weeks. Nerve symptoms are slower: in early cases, burning and tingling often begin to ease within days to a few weeks; in longstanding or severe neuropathy, improvement can take months, and some numbness may persist permanently. While levels are being corrected, doctors also watch for a drop in potassium and for coexisting folate deficiency.
For most people, prevention is straightforward: eat B12-rich foods regularly, and supplement if you are in a risk group. The daily value for B12 is 2.4 mcg, and it is easy to cover from food alone — unless you are vegan or have an absorption problem.
| Food | Serving | B12 (mcg) |
|---|---|---|
| Clams, cooked | 85 g (3 oz) | 84.1 |
| Beef liver, cooked | 85 g (3 oz) | 70.7 |
| Salmon (Atlantic), cooked | 85 g (3 oz) | 2.6 |
| Tuna, canned in water | 85 g (3 oz) | 2.5 |
| Ground beef | 85 g (3 oz) | 2.4 |
| Fortified nutritional yeast | 1 tbsp | 2.4 |
| Milk | 1 cup (240 ml) | 1.2 |
| Plain yogurt | 1 cup (245 g) | 1.1 |
| Swiss cheese | 30 g (1 oz) | 0.9 |
| Egg, whole | 1 large | 0.6 |
Additional prevention tips: vegans should use fortified foods and a daily supplement; people over 60 and long-term metformin or PPI users should have B12 checked periodically; and if you have pernicious anaemia, maintenance injections are not optional. Finally, treat the underlying cause — restoring B12 while a malabsorption problem continues will only delay the recurrence of symptoms.
Yes. Serum B12 reflects circulating levels, and cells can still be short of usable B12 — a "functional deficiency." If symptoms persist with a borderline or low-normal result, ask your doctor about methylmalonic acid (MMA) and homocysteine, which detect tissue-level deficiency more sensitively.
In early cases, tingling and burning often begin to ease within days to a few weeks. If the neuropathy is longstanding or severe, improvement can take months, and some numbness may remain. Nerve regeneration is slow, so judge progress over weeks rather than days.
For pernicious anaemia and severe malabsorption, injections are the standard — usually lifelong. For dietary deficiency, high-dose oral cyanocobalamin (1000–2000 mcg daily) is effective for most people because a small amount is absorbed passively. The right choice depends on the cause, so follow your doctor's guidance.
Diabetes, heavy alcohol use, thyroid disease, kidney disease, folate or B6 deficiency, and certain medications can all cause burning feet. Because the causes overlap, a proper medical work-up — not self-diagnosis — is the safest route.