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Your vitamin B6 came back high and you never bought a B6 supplement. Check your magnesium.

Vitamin B6 is added to magnesium, zinc, B-complex and multivitamin products, and to some foods and drinks. Doses stack without anyone noticing. How much is too much depends on which country's limit you read, and they differ by a factor of ten.

The gist
Australia's medicines regulator says consumers often do not know B6 is in their magnesium, zinc, B vitamin and multivitamin products.
Limits disagree tenfold: the US upper limit is 100 mg a day, the EU's is 12 mg, and the NHS says no more than 10 mg a day from supplements.
Too much B6 causes peripheral neuropathy, which the NHS describes as loss of feeling in the arms and legs.
Australia had logged 285 adverse event reports of B6-linked neuropathy by February 2026, and restricts higher-dose products from June 2027.
If your B6 result is high, add up the B6 in every product you take before anything else. That is the TGA's own advice to doctors.

B6 turns up in products sold for something else. In February 2026, Australia's Therapeutic Goods Administration told GPs to "take action now" on vitamin B6 toxicity. As reported by the RACGP's newsGP, the TGA flagged that consumers are often unaware B6 is in B vitamins, multivitamins, and magnesium and zinc products, as well as in foods and drinks with added B6. RMIT researchers writing in The Conversation add ageing-support, skin and hair products, and effervescent vitamin tablets. Most single products contain less than 50 mg a day. The problem is stacking: a magnesium product, a B-complex and an energy tablet can each look modest on their own.

The limits disagree by a factor of ten. The US upper limit for adults is 100 mg a day. According to the NIH Office of Dietary Supplements, the Food and Nutrition Board set it by halving a 200 mg dose that long-term studies had not linked to nerve damage. In 2023 the European Food Safety Authority cut its upper limit to 12 mg a day, naming peripheral neuropathy as the effect it is protecting against, and noted that people in the EU are unlikely to exceed it unless they take high-dose supplements. The NHS tells UK adults not to take more than 10 mg a day from supplements unless a doctor advises it. The NHS adds that 200 mg or more a day can cause loss of feeling in the arms and legs, and that the effect of doses between 10 mg and 200 mg is unclear. A 50 mg product is within the US limit and more than four times the EU one.

Australia is where the harm has been counted. According to newsGP, the TGA had received 285 adverse event reports of peripheral neuropathy linked to vitamin B6 products by 12 February 2026, and medicines with more than 10 mg a day have carried a neuropathy warning since March 2022. The TGA's rescheduling decision takes effect on 1 June 2027. Products with 50 mg a day or less stay on general sale. Products with more than 50 mg and up to 200 mg will need a pharmacist's advice. Anything above 200 mg will need a prescription. Adverse event reports show that harm was reported. They do not tell you how common it is among the people taking these products.

What the symptoms look like. The NIH fact sheet describes B6 toxicity as a sensory neuropathy, affecting the nerves that carry feeling. The NHS describes it as a loss of feeling in the arms and legs. The TGA advice to GPs reported by newsGP was to consider B6 toxicity in anyone presenting with symptoms of peripheral neuropathy and to review their total B6 intake from all sources.

What to do with your own result. If a blood test shows high vitamin B6, gather every supplement, powder, effervescent tablet and fortified drink you use. Read the vitamin B6 (pyridoxine) line on each label and add up the daily total. Bring that number, along with the result, to your doctor. If you have tingling, numbness or burning in your hands or feet, say so, even if it seems minor. A repeat test after cutting back, agreed with your doctor, shows whether intake was the driver. If you take nothing that contains B6, that is a different conversation, and one to have with your doctor rather than a search engine.

Why this matters for you

Other supplements move specific markers too. See how supplements affect blood test results, and for numbness or tingling specifically, the blood tests worth running first.

Disclaimer
This is commentary on published research, not medical advice. Talk to your doctor before changing anything based on a study.
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