Warnings high doses of vitamin B6 over a long period could cause irreversible nerve damage
In short:
Since 2020, the TGA has received 119 reports relating to peripheral neuropathy as a result of vitamin B6 poisoning.
Vitamin B6 is commonly available without a prescription but only those with confirmed deficiencies are required to take a supplement.
What's next:
The regulatory body is now considering an application to require B6 products to be stored behind the counter.
An over-the-counter supplement has ruined Dr Mary Buchanan's mobility and sense of freedom.
The 76-year-old spent four decades on her feet as an emergency physician.
Now in retirement, she struggles to walk short distances, up stairs or hills, suffering pain in her legs with depleted muscle strength and fatigue.
"It's changed my life in the way that my mobility has certainly been affected," Dr Buchanan told 7.30.
"That's not the sort of future I really want for myself, that I might be dependent on people before I may have needed to be."
The root cause of her debilitation has been traced to vitamin B6.
Vitamin B6 is vital for cognitive function but very few Australians are deficient in it. (ABC News: Jerry Rickard)
The vitamin is present in thousands of products in Australia as an additive — including medicines, multivitamin and mineral supplements, energy drinks and weight loss shakes — that is commonly available without a prescription and sold in supermarkets, health food shops, pharmacies, and online.
B6 is vital to cognitive function and only those with confirmed deficiencies are required to take a supplement.
In Dr Buchanan's case, she consumed it unknowingly.
B6 was one of the ingredients in a magnesium supplement she started taking in 2021 called 'Muscleze', a BioCeuticals product by Blackmores.
It was recommended to her by her pharmacist to help treat a genetic condition that gave her unbearable leg cramps and sleepless nights.
Dr Mary Buchanan began taking a magnesium supplement which also contained vitamin B6 in 2021. (ABC News)
After a few weeks, the daily doses appeared to be working.
Relief came. The leg twitching eased and sleep followed.
But then it went backwards, as if a mystery illness had taken over her body.
"Gradually over time, I sort of thought, 'Oh my gosh, I'm getting a bit weak, my legs seem to be getting weaker,'" Dr Buchanan said.
It got so bad, she feared she had Multiple Sclerosis or Motor Neurone Disease.
"The weakness continued so much so that I was having trouble going up, up and down stairs, and I could hardly walk 100 metres,"she said.
"And so I thought I probably have got something quite nasty, neurologically."
B6 toxicity
In March 2023, after two years of routinely taking the supplement, a neurologist diagnosed her with peripheral neuropathy, the result of vitamin B6 toxicity.
Cases of vitamin B6 poisoning are potentially very dangerous. (ABC News)
Tests revealed she had seven times the normal level of the vitamin in her system, which had damaged the nerve endings in her legs.
"I'd never heard of [B6 toxicity], my colleagues had never heard of it, my GP hadn't heard of it," Dr Buchanan told 7.30.
Dr Buchanan wrongly believed that the excess vitamin would be excreted from her system, but manufactured Vitamin B6 can survive in the body for up to 30 days.
"It was able to store in the neurological cells in my legs, and that caused irrecoverable damage to the nerves and also then to the muscles,"she said.
"I did feel angry when I looked at the literature and found there's no particular reason why B6 is combined with magnesium.
"People have got to be very wary of what is in supplementary medicines."
In a statement to 7.30 BioCeuticals said its B6 products "meet the stringent regulatory requirements of the TGA" and while it notes "adverse reactions can happen", it thoroughly investigates and addresses any reports raised.
"Consumers should consult their healthcare professional before taking multiple products containing vitamin B6," it said.
Dr Buchanan told 7.30 'Muscleze' was the only supplement she was taking.
'Tip of the iceberg'
The Therapeutic Goods Administration (TGA) regulates supplements distributed in Australia and monitors side effects from approved products.
Since 2020 the body has received 119 reports related to vitamin B6 and peripheral neuropathy.
Health professionals suspect many more cases have gone unreported.
Senior Neurologist Professor Tissa Wijeratne is the chair of the World Federation of Neurology and believes these numbers are "just the tip of the iceberg."
Professor Tissa Wijeratne warned that peripheral neuropathy can have debilitating effects. (Supplied)
"You absolutely don't need additional vitamin B6 unless you are deficient due to a genetic or metabolic abnormality," he told 7.30.
"I can't understand why a variety of healthcare products continue to add B6 in considerably high doses, which I feel is completely unnecessary."
Professor Wijeratne said there are still many unknowns about peripheral neuropathy, but the worst cases, he says, could be as bad as "being paralysed".
"There are theories when this happens over long periods of time it can cause irreversible damage to the extent you may find it difficult to walk or find balance," he said.
Warnings described as inefficient
The Royal College of Pathologists of Australasia is one of several medical bodies that have issued warnings, observing an increase in patients presenting with peripheral neuropathy.
Since 2022 the TGA has required a warning label for listed medicines with more than 10mg of B6.
Dr Buchanan believes they're insufficient.
Since 2022 the TGA has required a warning label for listed medicines with more than 10mg of B6. (ABC News: Jerry Rickard)
"The TGA insisted that the warnings are there on the bottom, and the company's complied with that, but how useful the labels are, are totally beyond me," Dr Buchanan said.
"You really need to have super vision to be able to read them, they're such small prints."
The regulatory body told 7.30 it's now considering an application to require B6 products containing between 5 mg and 200 mg to be stored behind the counter "to prevent physical access by the public" and to be sold only by pharmacists.
Doctor warns most supplements 'do nothing'
Such a change would be noticed by a majority of Australians.
Dr Michael Bonning from the Australian Medical Association says more than 50 per cent of the population takes a supplement regularly.
"And for most of those people, it does nothing — it doesn't help their health at all," he told 7.30.
Dr Bonning said over-consuming vitamins can make you sick, yet there's still a perception that vitamin supplements are harmless.
Michael Bonning says most people get all the vitamins they need from their daily diet. (ABC News: Rahni Sadler)
"People are thinking that more is better, when in actual fact, most people's diets most of the time contain all the vitamins they need," he told 7.30.
"We know that most of that goes straight through you and comes out in your urine and is of no benefit to you, so for the most part you are just spending money to create very expensive urine."
Dr Bonning warned social media is "rife with influencers" trying to convince the public they need supplements to improve their diets.
"Usually because they also have a financial interest in wanting those supplements to be sold," he said.
A multi-billion dollar industry
Supplements are big business in Australia.
According to the peak body, 75 per cent of Australian households use complementary medicines, including vitamin and dietary supplements.
The sector itself is now valued at $6.2 billion..
Dietary and vitamin supplements are a growing market now worth more than $6 billion. (ABC News: Jerry Rickard)
Performance coach Lucas Aoun is the son of a pharmacist and studied as a naturopath. He says the supplements he takes, and recommends are based on science.
"There's definitely products out there that I do know are not actually contained in the right quantities and the right dosages," Mr Aoun told 7.30
"I know individuals are actually thinking that it's having a positive effect on their biology, but deep down, if we had to actually analyse the supplement, there's a pretty good chance that there's actually no active constituent."
"Placebo has actually been the reason why they've gotten better."
Mr Aoun has created a name for himself in the world of 'biohacking' and alternative medicines — namely in the United States.
Lucas Aoun is a Melbourne-based performance coach who sells supplements online to clients. (ABC News: Matthew Holmes)
"A lot of the different supplements that I've prescribed, I've seen, you know, move the needle in terms of blood test results, and I've also seen massive improvements with patient symptoms and also how they're feeling in general, and a lot of that is actually due to some of the objective tests and measurements that I've put in place," he said.
"If a consumer is wanting to know whether or not a brand is legitimate, it's always important for them to look for third-party testing, which means that the product has been tested by an external company to verify the quality and purity of that product."
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