Quick answer

Yes, at high doses taken for a long time. NIH says 1 to 6 g of pyridoxine a day for 12 to 40 months can cause severe sensory neuropathy, and symptoms usually stop when the supplement stops. Europe's upper limit of 12 mg a day is far below the US limit of 100 mg. Ask your doctor about numbness.^1,2

Key facts

NIH says 1 to 6 g of pyridoxine a day for 12 to 40 months can cause severe, progressive sensory neuropathy, with loss of control of body movements.^1,3
NIH says the symptoms usually stop if the supplement is stopped as soon as they appear.¹
Some reports describe neuropathy at less than 500 mg a day, while studies of people taking about 200 mg a day for up to 5 years found none.¹
The European Food Safety Authority set an upper limit of 12 mg a day for adults in 2023, based on peripheral neuropathy, with 50 mg a day as its reference point.²
NIH says high intakes of vitamin B6 from food have not been reported to cause harm.¹

What do NIH's fact sheets say about B6 and nerve damage?

NIH's consumer fact sheet says people almost never get too much vitamin B6 from food, but that taking high amounts from supplements for a year or longer can cause severe nerve damage, leading people to lose control of their bodily movements, and that the symptoms usually stop when they stop taking the supplements.³

Taking 1 to 6 g of pyridoxine a day for 12 to 40 months can cause severe, progressive sensory neuropathy, with loss of control of body movements. The symptoms usually stop if the supplement is stopped as soon as they appear.^1,3

Some reports describe sensory neuropathy at less than 500 mg a day, while studies of people taking about 200 mg a day for up to 5 years found none. The European panel took 50 mg a day, from a case-control study, as its reference point for nerve harm.^1,2

Why do the US and Europe set such different limits?

The two limits draw on the same effect but weigh the uncertainty differently. The US Food and Nutrition Board noted that although several reports show neuropathy at doses below 500 mg a day, studies of patients treated with an average of 200 mg a day for up to 5 years found no such effect. Because the data on long-term harm were limited, the board halved that dose to set a limit of 100 mg a day for adults.¹

The European Food Safety Authority's 2023 opinion drew on systematic reviews of the literature and called the link between excess B6 and peripheral neuropathy well established. It could not identify a lowest observed effect level from human data, took 50 mg a day from a case-control study as a reference point, applied an uncertainty factor of 4, and combined this with an estimate from a dog study to set 12 mg a day for adults, including pregnant and lactating women.²

How the US and European limits for vitamin B6 were set^1,2
Authority	Upper limit a day	How it was set
US Food and Nutrition Board (via NIH)	100 mg	Half of about 200 mg a day, where studies up to 5 years found no neuropathy
European Food Safety Authority, 2023	12 mg	Reference point of 50 mg a day from a case-control study, an uncertainty factor of 4, and a dog study

What do the sources describe as signs of too much B6?

NIH describes severe and progressive sensory neuropathy characterized by ataxia, meaning loss of control of bodily movements, at the highest amounts. Other effects of too much vitamin B6 include painful and disfiguring skin patches, sensitivity to sunlight, nausea and heartburn.^1,3

Other effects of too much vitamin B6 include painful, disfiguring skin patches, sensitivity to sunlight, nausea and heartburn.^1,3

Because these effects are reported as dose dependent, with severity tracking the amount taken, NIH's guidance is that people taking B6 for medical reasons should be under a doctor's care.¹

Where can a lot of B6 come from?

NIH says high intakes of vitamin B6 from food have not been reported to cause harm, so the concern is supplements. The body absorbs large doses of B6 well but passes most of the excess in urine. NIH notes that B6 is sold in multivitamins, in supplements with other B vitamins and as a stand-alone supplement, and the limits count every source together.¹

High intakes of vitamin B6 from food have not been reported to cause harm.^1,3

Who should ask a doctor about vitamin B6 and nerve damage?

Anyone who notices numbness, tingling or unsteadiness while taking vitamin B6, since NIH describes sensory neuropathy and loss of control of body movements as its effects at high amounts.¹
Anyone taking B6 in amounts above the upper limit under a doctor's direction, who should keep that doctor informed of other supplements.¹
Anyone taking more than one product that contains B6, to add up the total.¹
Anyone who takes an anti-seizure medicine such as phenytoin, phenobarbital, carbamazepine or valproic acid, or levodopa, which NIH lists as interacting with B6.¹

Questions people ask

Does vitamin B6 cause neuropathy?

NIH says 1 to 6 g of pyridoxine a day for 12 to 40 months can cause severe sensory neuropathy, and EFSA calls the link well established. Reports exist at lower amounts. Ask your doctor if you have numbness or tingling.^1,2

How much vitamin B6 causes nerve damage?

No single threshold exists. NIH describes reports below 500 mg a day and studies at about 200 mg a day for up to 5 years with none, and EFSA took 50 mg a day as its reference point. Ask your doctor or pharmacist about your total.^1,2

Can vitamin B6 nerve damage be reversed?

NIH says the symptoms usually stop if the supplement is stopped as soon as they appear. The sources checked do not say how complete recovery is. Ask your doctor.¹

Can you get too much vitamin B6 from food?

NIH says people almost never get too much vitamin B6 from food or drinks, and that high intakes from food have not been reported to cause harm.^1,3

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Sources

This page is information, not medical advice. Talk to your doctor or pharmacist about your own situation.