
Vitamin B6 is essential – but too much can be toxic. Here’s what to know to stay safe
10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.
In recent weeks, reports have been circulating about severe reactions in people who’ve taken over-the-counter vitamin B6 supplements.
Vitamin B6 poisoning can injure nerves and lead to symptoms including numbness, tingling and even trouble walking and moving.
In some cases, those affected didn’t know the product contained any vitamin B6.
So what is vitamin B6, where is it found and how much is too much? Here’s what you need to know about this essential nutrient.
What is vitamin B6?
Vitamin B6 (also known as pyridoxine) is a group of six compounds that share a similar chemical structure.
It is an essential nutrient, meaning we need it for normal body functions, but we can’t produce it ourselves.
Adults aged 19–50 need 1.3mg of vitamin B6 per day. The recommended dose is lower for teens and children, and higher for those aged 51 and over (1.7mg for men and 1.5mg for women) and people who are breastfeeding or pregnant (1.9mg).
Most of us get this in our diet – largely from animal products, including meat, dairy and eggs.
The vitamin is also available in a range of different plant foods, including spinach, kale, bananas and potatoes, so deficiency is rare, even for vegetarians and vegans.
The vitamin B6 we consume in the diet is inactive, meaning the body can’t use it. To activate B6, the liver transforms it into a compound called pyridoxal-5’-phosphate (PLP).
In this form, vitamin B6 helps the body with more than 140 cellular functions, including building and breaking down proteins, producing red blood cells, regulating blood sugar and supporting brain function.
Vitamin B6 is important for overall health and has also been associated with reduced cancer risk and inflammation.
Despite being readily available in the diet, vitamin B6 is also widely included in various supplements, multivitamins and other products, such as Berocca and energy drinks.
Should we be worried about toxicity?
Vitamin B6 toxicity is extremely rare. It almost never occurs from dietary intake alone, unless there is a genetic disorders or disease that stops nutrient absorption (such as coeliac disease).
This is because all eight vitamins in the B group are water-soluble. If you consume more of the vitamin than your body needs, it can be excreted readily and harmlessly in your urine.
However, in some rare cases, excessive vitamin B6 accumulates in the blood, resulting in a condition called peripheral neuropathy. We’re still not sure why this occurs in some people but not others.
Peripheral neuropathy occurs when the sensory nerves – those outside our brain and spinal cord that send information to the central nervous system – are damaged and unable to function. This can be caused by a wide range of diseases (and is most well known in type 2 diabetes).
The most common symptoms are numbness and tingling, though in some cases patients may experience difficulty with balance or walking.
We don’t know exactly how excess vitamin B6 causes peripheral neuropathy, but it is thought to interfere with how the neurotransmitter GABA sends signals to the sensory nerves.
Vitamin B6 can cause permanent damage to nerves. Studies have shown symptoms improved when the person stopped taking the supplement, although they didn’t completely resolve.
What is considered excessive? And has this changed?
Toxicity usually occurs only when people take supplements with high doses of B6.
Until 2022, only products with more than 50mg of vitamin B6 were required to display a warning about peripheral neuropathy. But the Therapeutic Goods Administration lowered this and now requires any product containing more than 10mg of vitamin B6 to carry a warning.
The Therapeutic Goods Administration has also halved the daily upper limit of vitamin B6 a product can provide – from 200mg to 100mg.
These changes followed a review by the administration, after receiving 32 reports of peripheral neuropathy in people taking supplements. Two thirds of these people were taking less than 50mg of vitamin B6.
The Therapeutic Goods Administration acknowledges the risk varies between individuals and a lot is unknown. Its review could not identify a minimum dose, duration of use or patient risk factors.
But I thought B vitamins were good for me?
Too much of anything can cause problems.
The updated guidelines are likely to significantly lower the risk of toxicity. They also make consumers more aware of which products contain B6, and the risks.
The Therapeutic Goods Administration will continue to monitor evidence and revise guidelines if necessary.
While vitamin B6 toxicity remains very rare, there are still many questions about why some people get peripheral neuropathy with lower dose supplements.
It could be that some specific vitamin B compounds have a stronger effect, or some people may have genetic vulnerabilities or diseases which put them at higher risk.
So what should I do?
Most people don’t need to actively seek vitamin B6 in supplements.
However, many reports to the Therapeutic Goods Administration were of vitamin B6 being added to supplements labelled as magnesium or zinc – and some weren’t aware they were consuming it.
It is important to always check the label if you are taking a new medicine or supplement, especially if it hasn’t been explicitly prescribed by a health-care professional.
Be particularly cautious if you are taking multiple supplements. While one multivitamin is unlikely to cause an issue, adding a magnesium supplement for cramping, or a zinc supplement for cold and flu symptoms, may cause an excessive vitamin B6 dose over time, and increase your risk.
Importantly, pay attention to symptoms that may indicate peripheral neuropathy, such as pins and needles, numbness, or pain in the feet or hands, if you do change or add a supplement.
Most importantly, if you need advice, you should talk to your doctor, dietitian or pharmacist.
Vasso Apostolopoulos, Distinguished Professor, Professor of Immunology, RMIT University and Jack Feehan, Vice Chancellors Senior Research Fellow in Immunology, RMIT University
This article is republished from The Conversation under a Creative Commons license. Read the original article.
Don’t Forget…
Did you arrive here from our newsletter? Don’t forget to return to the email to continue learning!
Recommended
Learn to Age Gracefully
Join the 98k+ American women taking control of their health & aging with our 100% free (and fun!) daily emails:
-
The Great Cholesterol Myth, Revised and Expanded – by Dr. Jonny Bowden and Dr. Stephen Sinatra
10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.
The topic of cholesterol, and saturated fat for that matter, is a complex and often controversial one. How does this book treat it?
With strong opinions, is how—but backed by good science. The authors, a nutritionist and a cardiologist, pull no punches about outdated and/or cherry-picked science, and instead make the case for looking at what, statistically speaking, appear to be the real strongest risk factors.
So, are they advocating for Dave Asprey-style butter-guzzling, or “the carnivore diet”? No, no they are not. Those things remain unhealthy, even if they give some short-term gains (of energy levels, weight loss, etc).
They do advocate, however, for enjoying saturated fats in moderation, and instead of certain polyunsaturated seed oils that do far worse. They also advocate strongly for avoiding sugar, stress, and (for different reasons) statins (in most people’s cases).
They also demystify in clear terms, and often with diagrams and infographics, the various kinds of fats and their components, broken down in far more detail than any other pop-science source this reviewer has seen.
Bottom line: if you want to take a scientific approach to heart health, this book can help you to focus on what will actually make the biggest difference.
Share This Post
-
A Deeper Dive Into Seaweed
10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.
We wrote briefly about nori yesterday, when we compared it with well-known superfood spirulina. In nutritional terms, it blew spirulina out of the water:
Spirulina vs Nori – Which Is Healthier?
We also previously touched on it here:
21% Stronger Bones in a Year at 62? Yes, It’s Possible (No Calcium Supplements Needed!) ← nori was an important part of the diet enjoyed here
What is nori?
Nori is a seaweed, but that can mean lots of different things. In nori’s case, it’s an aggregate of several kinds of red algae that clump together in the sea.
When dried and/or toasted (which processes improve* the nutritional value rather than diminishing it, by the way), it looks dark green or dark purple to black in color.
*Effects of pan- and air fryer-roasting on volatile and umami compounds and antioxidant activity of dried laver (Porphyra dentata) ← this is nori, by another name
If you enjoy sushi, nori is the dark flat sheety stuff that other things are often wrapped in.
The plant that has animal nutrients
As established in the head-to-head we linked above, nori is a nutritional powerhouse. But not only is it very full of the perhaps-expected vitamins and minerals, it also contains:
Omega-3 fatty acids, including EPA, which plants do not normally have (plants usually have just ALA, which the body can convert into other forms including EPA). While ALA is versatile, having EPA in food saves the body the job of converting it, and thus makes it more readily bioavailable. For more on the benefits of this, see:
What Omega-3 Fatty Acids Really Do For Us
Iodine, which land plants don’t generally have, but seaweed usually does. However, nori contains less iodine than other kinds of seaweed, which is (counterintuitively) good, since other kinds of seaweed often contain megadoses that go too far the other way and can cause different health problems.
- Recommended daily amount of iodine: 150µg ← note that’s micrograms, not milligrams
- One 10g serving of dried nori contains: 232µg ← this is good
- Tolerable daily upper limit of iodine: 1,100µg (i.e: 1.1mg)
- One 10g serving of dried kombu (kelp) contains: 13,270µg (i.e: 13.3mg) ← this is far too much; not good!
So: a portion of nori puts us into the healthiest spot of the range, whereas a portion of another example seaweed would put us nearly 13x over the tolerable upper limit.
For why this matters, see:
- 8 Signs Of Iodine Deficiency You Might Not Expect
- Foods For Managing Hypothyroidism (incl. Hashimoto’s)
- Eat To Beat Hyperthyroidism!
As you might note from the mentions of both hypo- and hyperthyroidism, (which are exacerbated by too little and too much iodine, respectively) hitting the iodine sweet spot is important, and nori is a great way to do that.
Vitamin B12, again not usually found in plants (most vegans supplement, often with nutritional yeast, which is technically neither an animal nor a plant). However, nori scores even higher:
Vitamin B12-Containing Plant Food Sources for Vegetarians
Beyond nutrients
Nori is also one of the few foods that actually live up the principle of a “detox diet”, as it can help remove toxins such as dioxins:
Detox diets for toxin elimination and weight management: a critical review of the evidence
It’s also been…
❝revealed to have anti-aging, anti-cancer, anti-coagulant, anti-inflammatory, anti-microbial, anti-oxidant, anti-diabetic, anti-Alzheimer and anti-tuberculose activities.❞
~ Dr. Şükran Çakir Arica et al.
Read: A study on the rich compounds and potential benefits of algae: A review
(for this to make sense you will need to remember that nori is, as we mentioned, an aggregate of diverse red algae species; in that paper, you can scroll down to Table 1, and see which species has which qualities. Anything whose name starts with “Porphyra” or “Porphridum” is found in nori)
Is it safe?
Usually! There are two potential safety issues:
- Seaweed can, while it’s busy absorbing valuable minerals from the sea, also absorb heavy metals if there are such pollutants in the region. For this reason, it is good to buy a product with trusted certifications, such that it will have been tested for such along the way.
- Seaweed can, while it’s busy absorbing things plants don’t usually have from the sea, also absorb allergens from almost-equally-small crustaceans. So if you have a seafood allergy, seaweed could potentially trigger that.
Want to try some?
We don’t sell it, but here for your convenience is an example product on Amazon 😎
Enjoy!
Share This Post
-
The Diet Myth – by Dr. Tim Spector
10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.
Why are we supposed to go low-carb, but get plenty of whole grains? Avoid saturated fat, but olive oil is one of the healthiest fats around? Will cheese kill us or save us? Even amongst the well-informed, there’s a lot of confusion. This book addresses these and many such topics.
A main theme of the book is howa lot of it relates to the state of our gut microbiome, and what is good or bad for that. He also discusses, for example, how microbes predict obesity better than genes, and the good news is: we can change our microbes a lot more easily than we can change our genes!
In the category of criticism, he repeats some decades-old bad science in some areas outside of his field (i.e. unrelated to nutrition), so that’s unfortunate, and/but doesn’t detract from the value of the book if we keep to the main topic.
Bottom line: if you’d like to understand better the physiology and microbiology behind why dieting does work for most people (and how to do it better), then this is a great book for that.
Click here to check out The Diet Myth, and learn the science behind the confusion!
Share This Post
Related Posts
-
With Medical Debt Burdening Millions, a Financial Regulator Steps In to Help
10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.
When President Barack Obama signed legislation in 2010 to create the Consumer Financial Protection Bureau, he said the new agency had one priority: “looking out for people, not big banks, not lenders, not investment houses.”
Since then, the CFPB has done its share of policing mortgage brokers, student loan companies, and banks. But as the U.S. health care system turns tens of millions of Americans into debtors, this financial watchdog is increasingly working to protect beleaguered patients, adding hospitals, nursing homes, and patient financing companies to the list of institutions that regulators are probing.
In the past two years, the CFPB has penalized medical debt collectors, issued stern warnings to health care providers and lenders that target patients, and published reams of reports on how the health care system is undermining the financial security of Americans.
In its most ambitious move to date, the agency is developing rules to bar medical debt from consumer credit reports, a sweeping change that could make it easier for Americans burdened by medical debt to rent a home, buy a car, even get a job. Those rules are expected to be unveiled later this year.
“Everywhere we travel, we hear about individuals who are just trying to get by when it comes to medical bills,” said Rohit Chopra, the director of the CFPB whom President Joe Biden tapped to head the watchdog agency in 2021.
“American families should not have their financial lives ruined by medical bills,” Chopra continued.
The CFPB’s turn toward medical debt has stirred opposition from collection industry officials, who say the agency’s efforts are misguided. “There’s some concern with a financial regulator coming in and saying, ‘Oh, we’re going to sweep this problem under the rug so that people can’t see that there’s this medical debt out there,’” said Jack Brown III, a longtime collector and member of the industry trade group ACA International.
Brown and others question whether the agency has gone too far on medical billing. ACA International has suggested collectors could go to court to fight any rules barring medical debt from credit reports.
At the same time, the U.S. Supreme Court is considering a broader legal challenge to the agency’s funding that some conservative critics and financial industry officials hope will lead to the dissolution of the agency.
But CFPB’s defenders say its move to address medical debt simply reflects the scale of a crisis that now touches some 100 million Americans and that a divided Congress seems unlikely to address soon.
“The fact that the CFPB is involved in what seems like a health care issue is because our system is so dysfunctional that when people get sick and they can’t afford all their medical bills, even with insurance, it ends up affecting every aspect of their financial lives,” said Chi Chi Wu, a senior attorney at the National Consumer Law Center.
CFPB researchers documented that unpaid medical bills were historically the most common form of debt on consumers’ credit reports, representing more than half of all debts on these reports. But the agency found that medical debt is typically a poor predictor of whether someone is likely to pay off other bills and loans.
Medical debts on credit reports are also frequently riddled with errors, according to CFPB analyses of consumer complaints, which the agency found most often cite issues with bills that are the wrong amount, have already been paid, or should be billed to someone else.
“There really is such high levels of inaccuracy,” Chopra said in an interview with KFF Health News. “We do not want to see the credit reporting system being weaponized to get people to pay bills they may not even owe.”
The aggressive posture reflects Chopra, who cut his teeth helping to stand up the CFPB almost 15 years ago and made a name for himself going after the student loan industry.
Targeting for-profit colleges and lenders, Chopra said he was troubled by an increasingly corporate higher-education system that was turning millions of students into debtors. Now, he said, he sees the health care system doing the same thing, shuttling patients into loans and credit cards and reporting them to credit bureaus. “If we were to rewind decades ago,” Chopra said, “we saw a lot less reliance on tools that banks used to get people to pay.”
The push to remove medical bills from consumer credit reports culminates two years of intensive work by the CFPB on the medical debt issue.
The agency warned nursing homes against forcing residents’ friends and family to assume responsibility for residents’ debts. An investigation by KFF Health News and NPR documented widespread use of lawsuits by nursing homes in communities to pursue friends and relatives of nursing home residents.
The CFPB also has highlighted problems with how hospitals provide financial assistance to low-income patients. Regulators last year flagged the dangers of loans and credit cards that health care providers push on patients, often saddling them with more debt.
And regulators have gone after medical debt collectors. In December, the CFPB shut down a Pennsylvania company for pursuing patients without ensuring the debts were accurate.
A few months before that, the agency fined an Indiana company working with medical debt for violating collection laws. Regulators said the company had “risked harming consumers by pressuring or inducing them to pay debts they did not owe.”
With their business in the crosshairs, debt collectors are warning that cracking down on credit reporting and other collection tools may prompt more hospitals and doctors to demand patients pay upfront for care.
There are some indications this is happening already, as hospitals and clinics push patients to enroll in loans or credit cards to pay their medical bills.
Scott Purcell, CEO of ACA International, said it would be wiser for the federal government to focus on making medical care more affordable. “Here we’re coming up with a solution that only takes money away from providers,” Purcell said. “If Congress was involved, there could be more robust solutions.”
Chopra doesn’t dispute the need for bigger efforts to tackle health care costs.
“Of course, there are broader things that we would probably want to fix about our health care system,” he said, “but this is having a direct financial impact on so many Americans.”
The CFPB can’t do much about the price of a prescription or a hospital bill, Chopra continued. What the federal agency can do, he said, is protect patients if they can’t pay their bills.
KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF—an independent source of health policy research, polling, and journalism. Learn more about KFF.
USE OUR CONTENT
This story can be republished for free (details).
KFF Health News is a national newsroom that produces in-depth journalism about health issues and is one of the core operating programs at KFF—an independent source of health policy research, polling, and journalism. Learn more about KFF.
Subscribe to KFF Health News’ free Morning Briefing.
Don’t Forget…
Did you arrive here from our newsletter? Don’t forget to return to the email to continue learning!
Learn to Age Gracefully
Join the 98k+ American women taking control of their health & aging with our 100% free (and fun!) daily emails:
-
The Bare-Bones Truth About Osteoporosis
10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.
In yesterday’s issue of 10almonds, we asked you “at what age do you think it’s important to start worrying about osteoporosis?”, and here’s the spread of answers you gave us:
The Bare-bones Truth About Osteoporosis
In yesterday’s issue of 10almonds, we asked you “at what age do you think it’s important to start worrying about osteoporosis?”, and here’s the spread of answers you gave us:
At first glance it may seem shocking that a majority of respondents to a poll in a health-focused newsletter think it’ll never be an issue worth worrying about, but in fact this is partly a statistical quirk, because the vote of the strongest “early prevention” crowd was divided between “as a child” and “as a young adult”.
This poll also gave you the option to add a comment with your vote. Many subscribers chose to do so, explaining your choices… But, interestingly, not one single person who voted for “never” had any additional thoughts to add.
We loved reading your replies, by the way, and wish we had room to include them here, because they were very interesting and thought-provoking.
Let’s get to the myths and facts:
Top myth: “you will never need to worry about it; drink a glass of milk and you’ll be fine!”
The body is constantly repairing itself. Its ability to do that declines with age. Until about 35 on average, we can replace bone mineral as quickly as it is lost. After that, we lose it by up to 1% per year, and that rate climbs after 50, and climbs even more steeply for those who go through (untreated) menopause.
Losing 1% per year might not seem like a lot, but if you want to live to 100, there are some unfortunate implications!
About that menopause, by the way… Because declining estrogen levels late in life contribute significantly to osteoporosis, hormone replacement therapy (HRT) may be of value to many for the sake of bone health, never mind the more obvious and commonly-sought benefits.
On the topic of that glass of milk…
- Milk is a great source of calcium, which is useless to the body if you don’t also have good levels of vitamin D and magnesium.
- People’s vitamin D levels tend to directly correlate to the level of sun where they live, if supplementation isn’t undertaken.
- Plant-based milks are usually fortified with vitamin D (and calcium), by the way.
- Most people are deficient in magnesium, because green leafy things don’t form as big a part of most people’s diets as they should.
See also: An update on magnesium and bone health
Next most common myth: “bone health is all about calcium”
We spoke a little above about the importance of vitamin D and magnesium for being able to properly use that. But potassium is also critical:
Read more: The effects of potassium on bone health
While we’re on the topic…
People think of collagen as being for skin health. And it is important for that, but collagen’s benefits (and the negative effects of its absence) go much deeper, to include bone health. We’ve written about this before, so rather than take more space today, we’ll just drop the link:
We Are Such Stuff As Fish Are Made Of
Want to really maximize your bone health?
You might want to check out this well-sourced LiveStrong article:
Bone Health: Best and Worst Foods
(Teaser: leafy greens are in 2nd place, topped by sardines at #1—where do you think milk ranks?)
Don’t Forget…
Did you arrive here from our newsletter? Don’t forget to return to the email to continue learning!
Learn to Age Gracefully
Join the 98k+ American women taking control of their health & aging with our 100% free (and fun!) daily emails:
-
The Diet Myth – by Dr. Tim Spector
10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.
Why are we supposed to go low-carb, but get plenty of whole grains? Avoid saturated fat, but olive oil is one of the healthiest fats around? Will cheese kill us or save us? Even amongst the well-informed, there’s a lot of confusion. This book addresses these and many such topics.
A main theme of the book is howa lot of it relates to the state of our gut microbiome, and what is good or bad for that. He also discusses, for example, how microbes predict obesity better than genes, and the good news is: we can change our microbes a lot more easily than we can change our genes!
In the category of criticism, he repeats some decades-old bad science in some areas outside of his field (i.e. unrelated to nutrition), so that’s unfortunate, and/but doesn’t detract from the value of the book if we keep to the main topic.
Bottom line: if you’d like to understand better the physiology and microbiology behind why dieting does work for most people (and how to do it better), then this is a great book for that.
Click here to check out The Diet Myth, and learn the science behind the confusion!
Don’t Forget…
Did you arrive here from our newsletter? Don’t forget to return to the email to continue learning!
Learn to Age Gracefully
Join the 98k+ American women taking control of their health & aging with our 100% free (and fun!) daily emails: