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Vitamin B6 and B12 Supplements Appear to Cause Cancer in Men (theatlantic.com)
206 points by simulate on Oct 26, 2017 | hide | past | favorite | 108 comments

As far as I understand, it is well documented that smoking correlates with B12 deficiency, and so many smokers take this vitamin as a supplement to make themselves feel better about their smoking habits.

This study then showed, not just that people got cancer, but they got lung cancer. This study was not a randomized trial that can show causation: it was a cohort study, where they ask a bunch of questions about peoples' past or ongoing behavior and then look for correlations from which you can try to guess at potential causes.

In a cohort study, there are attempts to predict confounding variables and "control" for them, but this involves essentially assuming the result and backing out the math, and assumes you trust that the participant is giving you correct data anyway.

A really fun confounding variable you get in these kinds of studies is that people who even bother to do your study correctly are also people who probably listen to their doctor and brush their teeth and wear their seatbelts and generally lead a safer life. (I am forgetting the name of this, but it is something like "compliance effect"?)

Further, if you have participants who don't just answer poorly but actively lie in ways that are correlated with the variables you care about (maybe "another way I make myself feel better about my smoking habit is to pretend I smoke half as much as I do or also smoke cigars and not count them"), you are effectively going to have no hope of "controlling" for that in the way you can with a blinded randomized controlled trial.

Given this, I read this and only think "that's an interesting hypothesis that is now worth digging into with real science to figure out what is going on", not "OK, everyone should stop taking B12 supplements if they don't want to end up randomly getting lung cancer"... that is just way too specific and too predictable of a cancer to be associated with this particular supplement.

But the article says:

> Among people who smoke, the effect appeared to be synergistic, with B6 usage increasing risk threefold. The risk was even worse among smokers taking B12. Using more than 55 micrograms daily appeared to almost quadruple lung-cancer risk.

> There was no apparent risk among women—which is not to say it doesn’t exist, only that it wasn’t apparent.

Which would appear to rule out smoking as a confounder, except until you realise that people who smoke more might be more likely to take vitamin B6 - maybe because they are actually diagnosed deficient and not just trying to make themselves feel better - and that maybe B12 deficiency might be associated with higher levels of smoking as compared to lower levels (if higher levels of smoking are required for B12 deficiency than B6 , and the deficiencies are similarly diagnosed and not just feel-good vitamin supplementation). i.e. "smoking" isn't a binary category.

And the gender thing would be really surprising if the cancer was only caused by smoking - unless we know that smoking doesn't cause B6 or B12 deficiency in women, then that would also appear to remove smoking as a confounder.

In conclusion, maybe.

Hard to tell much about B vitamin supplement effects on non-smokers from this study.

Researchers themselves excluded never-smokers from more detailed stratified analysis because of their small number.

There were only 60 cases of lung cancer in never-smoker category (out of 36,381 people => 0.16%).

In comparison there were 748 cases of lung cancer in smoker categories (former + recent + current) (out of 40,737 people => 1.84%).

So there is 11.5x higher risk of lung cancer simply by smoking (including people who stopped smoking).

For comparison the highest hazard ratio from this study was 3.71x for a category of current smoker taking >55ug/d B12 vs current smoker who is non-user of B12.


Also curiously, the worse risks seem to be associated with people who stopped taking vitamins than people who currently use vitamins (B6: 1.97x vs 1.38x, B9: 1.65x vs 1.05x, B12: 2.58x vs 1.19x - individual supplement use status former vs current).

Plus smaller doses of B6/B9/B12 shown in this study to pretty much universally lower lung cancer risk by a bit (hazard ratios of 0.8-0.9x ranges; one noticeable outlier >600ug/d B9 in recent smokers halving risk of cancer).

Some people hate statistics for a reason, and this is the exact reason. It is outrageous how the author conveniently manipulated the data to support the claim in their paper.

For those of you who want to do your own analysis, assuming their data are authentic, take a look at their Table I:


Digging deeper into tables in the paper, I realized there is actually even less data about non-smokers than I thought.

Out of those 60 non-smokers with lung cancer apparently just 20 were men (out of 14,208 study participants who were men and non-smokers => 0.14%)



Curiously this also means non-smoking women have 1.28x higher chance to get lung cancer than non-smoking men (unrelated to vitamins).


For never-smokers vs smokers men risk ratios are then (again unrelated to vitamins):

- current smoker: 31.7x higher risk

- recent smoker (stopped < 10 years ago): 21.3x higher risk

- past smoker (stopped > 10 years ago): 8.9x higher risk


Take home message: stop smoking!

Precautionary principle: if you take B vitamin supplements, you can continue (for slight decrease of cancer risk), just make sure you aren't taking mega-doses (especially if you still smoke), but really - stop smoking - the sooner you do less cumulative harm you get.

I would also guess that smoker who experience health problems are more likely to start supplementing.

Isn't > 55 micrograms essentially anyone who takes a multi-vitamin?

Maybe it's just denial as I take one, but this study is a bit hard for me to believe.

Amounts of vitamins per supplement seem to vary wildly.

Just from checking supplements I have at home:

Supplement #1 (all B vitamins):

- B6: 4.2mg

- B9: 600ug

- B12: 7.5ug

Supplement #2 (just B6 + B9 + B12):

- B6: 75mg

- B9: 800ug

- B12: 150ug


Recommended daily doses are:

- B6: 1.7 mg/day (men)

- B9: 400 ug/day in US, 330 ug/day in EU (men + non-pregnant-non-lactating women)

- B12: 2.4 μg/day in US, 4.0 μg/day in EU (men + non-pregnant-non-lactating women)

Tolerable upper intake levels are:

- B6: 100 mg/day in US, 25 mg/day in EU

- B9: 1000 ug/day

- B12: no sufficient evidence for setting upper level


From the study:

Beneficial effects (for men):

- B6: 1.41 - 3mg/day, multivitamins

- B9: 200 - 400 mg/day

- B12: 0.1 - 55 ug/day

Harmful effects (for men):

- B6: > 20mg/day

- B9: 400 - 600 mg/day

- B12: > 55ug/day


Also something to keep in mind: apparently the majority of people in this study who got lung cancer were heavy smokers for many years, even if they stopped smoking.

Lung cancer by years of smoking:

- 0 years: 60 cases

- 1-35 years: 169 cases

- > 35 years: 568 cases

Lung cancer by pack-years of smoking:

- 0 pack-years: 60 cases

- 1-25 pack-years: 178 cases

- > 25 pack-years: 555 cases

Something else that seems to be overlooked here is that the cohort were folks who already had heart disease. Since smoking is heavily correlated with poor cardiac outcomes, I imagine a significant swath of that 6,837 cohort were likely to be smokers.

Even if they aren't smokers, taking an already sick test group and trying to draw general conclusions about certain inputs is madness. Epidemiology can be a great way to form hypotheses, but this entire discipline of research has been misapplied for the better part of a century now.

Exactly. Who's to say that low cardiac output isn't conducive to cancer formation or spread.

Humans are so complicated but these studies try to boil them down to some simple cause and effect relationship.

This is obviously my own anecdata, but up until about 2 years ago I smoked for close to 20 years. I've never once heard that B12 did anything to prevent cancer. No smoker I ever interacted with - and I interacted with thousands over the years I'm sure - has ever said or implied they took vitamins to offset their tobacco use.

I think the point that the op was trying to make was that smoking may cause a B12 deficiency. Having a deficiency may lead to taking a supplement.

I doubt anyone would be taking it to "prevent cancer", only to feel like they are doing something about the numerous health effects of smoking.


Off topic but, any tips on stopping? What method worked for you?

I was smoker for 9 years - I thought I enjoyed smoking, I can't live without it, etc. A friend recommended a book - Alan Carr's Easy Way. Tried quitting before and it never worked. After reading the book it didn't feel hard, it just made sense. Recommended the book to 2 friends who also quit. Give it a try.

I would also recommend this author's "Easy Way" book for quitting drinking, if that's something you're interested in. I read the book over the course of 2 days, and in that time experienced a complete paradigm shift wherein alcohol suddenly lost all appeal to me. Before then I knew drinking was causing me more harm than good, and I knew the deleterious effects of consuming it, yet I never felt compelled to do anything about it. After reading the book, drinking alcohol just didn't make sense to me anymore.

I'd just like to say that this helped my father who smoked for over 20 years.

Good book, but a little on the repetitive side. It didn't do it for me, but I think that's because a lot of the points he makes are things I already thought of constantly.

The repetition seemed like some form of deliberate hypnosis. I would read the repetitive parts and my mind would start to criticize how it could be so poorly written, and by the end of the book I had quit smoking after over 10 years and not even thinking I would ever even want to quit when I started the book. (and still quit after 10 more years)

What worked for me after trying (and failing) to quit cold turkey a few times was trying to smoke just a tiny bit less every week or two, maybe even every month, over a period of ~3 years.

The way I did this was by making it a bit harder/uncomfortable to get my cigarettes, and by tring to smoke just 1 cig less every period.

E.g. I would usually carry around a pack in my jeans, so I started leaving them at the car, so if I wanted to smoke it would be harder for me, so that would reduce the impulse when I was very busy or just didn't have the time. After some time doing that it was no longer a problem so I had to up the ante: I would only bring so many cigarettes with me and leave the rest at home. So if I knew I only had say 10, I would try to spread them over my working hours.

Then I would bring only 5 and so on. At some point, some 2 years later I would only smoke 1 in the mid-morning, 1 after lunch and 1 in the afternoon.

Then I would set myself to only have 1 after lunch. Then 1 every other day.

After that it was easier to go several days without smoking until one day I just didn't feel like buying more and I stopped.

Also, I think what worked quite good for me was to avoid "punishing" myself if for some reason I didn't make it one week and smoked a couple more, as long as I was kept reducing it overall the other weeks.

Doing it like this was easier for me I believe, because my own body was breaking the addiction so I just enjoyed smoking less and less, which I think it's why I couldn't do it cold turkey: my craving was stronger than my will. However reducing the craving over a long period allowed me to weaken that craving until my will to stop was stronger.

I know my method sounds a bit stupid if you phrase it like "how to quit smoking in 3 years", because everyone wants to do it NOW. But by avoiding such an unreachable (to me) goal, I managed to quit even if it took that long, so I am happy with the results :)

Hooe that helps.

This video is about quitting sugar, but it mentions a part from Alan Carr's book that helped my boyfriend quit smoking. Realizing it isn't making you calmer, but actually just restarting the cycle of ups and downs while steadily going downhill. (the part with the graph) https://youtu.be/olEMIohTgzQ?t=3m18s

Also for him he did the "don't break the chain" method. Bought a paper calendar, a pen, and a red and green marker. Week one was 8 cigarettes per day, week 2 was 7 cigarettes per day, etc. You write down that number with the black pen through the calendar so you know what your goal is. Exception being for 2 weeks you do 2 cigarettes per day, and for 3 weeks you do 1 cigarette per day because when it's that low you are fighting more of the mental aspect.

Then every day at the end of the day, exactly midnight you can put a a big green checkmark if you kept to the number, or a big red X if you didn't.

The idea is that you never want to break that chain of green checkmarks.

He hasn't smoked in a few years now. :)

2 months of using an e-cig/vape box, with a graduated decline in nicotine percentage.

Some people have success with electronic cigarettes: https://en.wikipedia.org/wiki/Electronic_cigarette#Smoking_c...

I have known a couple of people, including my father, who went through a program run by Seventh-Day Adventist hospitals. My father had smoked for about thirty years at the time. The other guy had probably smoked for about half that.

Get a high quality vape box and reduce the nicotine % of your liquid until you get to 0, and then you can just do it to help deal with the ritual/oral fixation aspect of it

did you normally ask smokers about their vitamin cocktails?

No, but smokers are masters of justification and excuses. Almost all smokers talk about with each other is wanting to stop smoking, and how bad it is for them.

Another issue is, they don't seem to differentiate between which B12 supplement. Cyanocobalamin may or may not have long term effects, and probably should be avoided as a supplement ingredient.

Although, someone always pops up and says "but there isn't enough cyanide to matter"; we don't know what supplementing with cyanocobalamin does over a decade actually does.

There is always MethylCobalamin that one can opt for. And also it's manifold more effective.

I switched from the more easily-swallowable cyanocobalamin to a sublingual methylcobalamin for this and the other reason.

My doctor also instructed me to eat more red meat. Anemia runs in my family (on the feminine side) to the point where my mother has had to have blood transfusions to save her life. I'm a male with a similar problem to a far lesser degree. While I aim to eat enough iron-rich foods, to boost the absorption I was also instructed to up my B12 intake as iron has traditionally been understood to be a bit easier to overdo. Food was always recommended over supplementation as well, but it's often not enough.

Also folate intake can mask B12 deficiency so it is always good idea to have buffer of Vitamin B12 in your body when starting on iron supplementation. The food will rarely help as in most cases B12 deficiency is not because of less B12 rich food is eaten but because our body can't absorb it properly. So sublingual and intramuscular intake is preferable.

For which reason, in spite of the potential inconclusiveness of these results, I am mildly concerned about the parent subject.

I used to be a smoker. After quitting and having some tests done by my doctor he said that my lungs should be back to functioning/health as if I'd never smoked inside of 4-5 years (so long as I didn't relapse. That hasn't been a problem). We didn't discuss chances of lung cancer in spite of that. If it's true that the supportive effects of B12 supplementation even on ex-smokers exponentially increases chances, then it becomes even more concerning.

I'll be watching for developments.

Nearly all studies that have shown a beneficial effect of B12 have been done with cyanocobalamin, though methylcobalamin is more bioavailable (ie. it's "absorbed better").

How many smokers are health conscious enough to know that they have a B12 deficiency but not health conscious enough to quit smoking?

Quitting smoking isn't done on consciousness alone. You can assume more health conscious people never start smoking, but then you are assuming people don't change.

Do you really think that the difficulty gap between taking a vitamin and quitting smoking is small? Id imagine there's quite a lot of daylight between people who are capable of quitting and people who are capable of taking a daily vitamin.

People with alcoholism should take a B1 supplement. They may take a multi B supplement. People with alcoholism would tend to smoke, a lot.

Lung cancer doesn't just affect smokers, though. People who have never smoked still have a lifetime risk of about 0.5%-1.0%. And the study was studying self-reported non-smokers in addition to smokers.

"We found that B6 and B12 had sex- and source-specific associations with lung cancer risk. In addition, the association in men was more pronounced in cigarette smokers."


Same aplies to drinking beer.

Participants took folic acid (lab created), not folate (the form found in nature) which has been shown to be far more absorbable. Folic acid also binds to the folate receptors, preventing folate from food being taken up. In people with MTHFR gene mutations, folic acid is contraindicated. Anyone with such mutations should be avoiding foods with added folic acid. Folate and folacin seem to be ok. MTHFR is already associated with increased cancer and heart disease.

No mention was made whether the participants had MTHFR mutations, perhaps because the cohorts started 20 years ago and cheap sequencing wasn't yet available.

All it tells is that more actual science needs to be done here. Also the article was classic poor science reporting with obvious bias.

This really needs to be at the top. It is something 40-60% of the population have MTHFR mutation. Given the size it is kind of surprising the marketing departments haven't started touting MTHFR safe foods on their packaging.

After learning about it from my 23andme results I now avoid regularly eating foods with added folic acid and take a supplement which can't be found at the grocery store because they will sell the lab created variety which can't be processed. After these changes various symptoms I have had all my life went away. But I can only guess what would happen if someone with MTHFR were taking the lab versions supplements every day for years.

Can you provide more information on the supplement and which symptoms you had disappear?


Thanks for pointing this out. It was the first thing I thought of after seeing the headline. I have family that mentioned they have a MTHFR mutation so I checked my 23andme results through genetic genie and I did indeed inherit a mutation from one of my parents.

I changed multivitamins to one without folic acid and supplement with methylfolate and methylcobalamin.

I feel like it has helped a bit, but not exactly sure. I am still experimenting with the amount of methylfolate I use. I think if I want to take is serious, I need to cut out caffeine completely. I definitely notice stamina issues when I drink coffee and take methylfolate. Caffeine also prevents B12 absorption with kind of defeats the point also.

I would definitely like to see more research done as it all kind of feels uncertain.

If you use 23andMe, you can get a methylation analysis here: https://geneticgenie.org/methylation-analysis/

I'm not connected with Genetic Genie, I'm only sharing a way I found to discover if I have the MTHFR mutation.

That site says 23andme stopped providing health information, but they clearly still offer the service. Are they not able to use the results from 23andme if it is recent?

Also, what led you to your curiosity of MTHFR? Are there other services you use to “hack your health”?

You have to download your raw genetic data from 23andMe and then re-upload it to get the methylation analysis. You can download your raw genetic data from 23andMe here: https://you.23andme.com/tools/data/download/

"Regular" people doesn't need in any way of to these B12 supplements, as there is plenty of it in animal products, which have already been taking B12 supplements all their lives. However, vegans need to take these supplements if they want their B12 intake, without animals as the intermediary.

As a side note: B12 is created by micro-organisms in the soil, making our vegetables and fruits completely covered of it. With our modern lifestyle, the soil is terribly poor of these micro-organisms and having cleaned-as-hell vegetables reduces even more the B12 we can find in these vegs.

Not only that, but B12 isn't actually produced by any of the animals which make up those "animal products" which allegedly have "plenty" of B12 in them. The animals, if they have B12, get it from eating vegetables which have bacteria on them.

These days, however, many animals destined for the dinner table are pumped full of antibiotics (which may kill those B12-producing bacteria), are fed other animals or sterilized grains/vegetables. So it is quite possible that the animals themselves aren't getting adequate B12, and as a result even animal eaters might have a B12 deficiency.

My own doctor recommends all his patients, whether or not they're vegetarian, take B12 supplements.

From wikipedia:

"Ruminants, such as cows and sheep, absorb B12 produced by bacteria in their guts"

Fun fact: Rabbits eat their fecal pellets (they have soft and hard poops, pellets are the hard ones). Those are filled with half digested plant matter. Since they are exposed to bacteria during the first digestion, those fecal pellets are full of vitamins. B12 is one of them. They often eat those dried pellets directly from their fur as breakfast to get the energy to start the day.

And how do the bacteria get there? Do they get there if they're fed sterilized food or other cows? And are the bacteria killed off by the antibiotics they're given?

> And how do the bacteria get there?

Pre-seeded during breast feeding, as happens across all mammals. How many billions of years do you want to go back on this question?

> And are the bacteria killed off by the antibiotics they're given?

Evidently not, as in developed country sick animals don't get turned into meat foods on principle and by law --- so they don't show up deficient. If they lived for 9 decades like we do, they might (or not). But they don't.

But you can just measure whether animal eaters (tend to) have a B12 deficiency or not - you don't need to know any of this. Is your doctor recommending this based off a long chain of reasoning or based off of a study just directly measuring the rates of B12 deficiency? Since the latter is much easier and is what you actually care about.

It is interesting that B12 in sufficient quantities is actually made by bacteria in the gut, but as it is not absorbed there (only small intestine can absorb that) it became a waste. It is probably one of the reasons that animals like dogs or gorillas eat their feces.

[1] http://www.veganhealth.org/b12/animal

Thanks for the website you linked, I was searching for something like this for a while now.

That is the reason rabbits will eat their fecal pellets.

My Crohn's disease impairs my ability to absorb nutrients, and so my doctor has instructed me to supplement several things, including B vitamins and calcium.

In the past he's given me prescriptions for these supplements, but these are vastly more expensive than the equivalent OTC versions (and yes, I've checked that it really is the equivalent molecule). So I'd hate to see new regulations that would increase my expenses just because some people believe in some kind of voodoo nutrition contrary to best practices.

I'm a single data point in this story.

I've been vegan since 1991. I also have Crohn's disease.

I had a bowel resection in 2001 and subsequently my B12 blood tests revealed a deficiency. I was then prescribed a course of monthly B12 injections. These went down to 3 monthly and for the last 5 years my yearly blood test have deemed them unnecessary.

However, I now have Vitamin D deficiency instead. Plus ça change.

Its worth noting that there are people who have b12 absorption deficiencies. My family has a history of it and a few are prescribed b12 injections once a month.

These injections are usually much higher than what you would take in pill for, as your body absorbs it easier and stores some for later.

Would be interested in more real science about the injections.

most factory farmed animals get their B12 from an injection

Do you have a source of this?

While this study is looking at lung cancer specifically, it's worth highlighting how much vitamin B6, b12 and other B-family are you getting via energy drinks. I'm currently hooled on Red Bull sugar free and I believe that long term consumption may be unhealthy for me due to elevated levels of B vitamins:


More likely that long-term consumption may be unhealthy for you due to the elevated levels of Red Bull sugar-free you're getting.

Try water.

Because anything called an energy drink must surely be bad for you.

It's very likely to be bad for you.

Alternative milk types(soy,rice..etc), breakfast cereals also have a lot of B12 supplemented

I'd be more worried about the caffeine, which we know increases demand for calcium and magnesium, and causes an increase in water excretion, among other negative effects.

I'd be more concerned that you are basically drinking poison.

Full text of the published study: http://ascopubs.org/doi/full/10.1200/JCO.2017.72.7735

Long-Term, Supplemental, One-Carbon Metabolism–Related Vitamin B Use in Relation to Lung Cancer Risk in the Vitamins and Lifestyle (VITAL) Cohort

IMO, Likely just statistical noise, but clearly worth further study.

Link only found among Men. 'Results from previous studies of an association of B vitamins with lung cancer risk are inconsistent.'

> There was no apparent risk among women—which is not to say it doesn’t exist, only that it wasn’t apparent.

Or it doesn't exist, or it even lowers the risk of cancer in women, or ...

I hate when something "not found" in some study is streched to fit some specific tone that the article wants.

As someone with an as yet unexplained B12 deficiency (meat eater, never-smoker, no intrinsic factor antibody) who gets injections via cyanocobalamin every other month I feel like I’ve just been hit with more FUD

Go about your day. This is not at the level of certainty to be actionable.

I'm surprised the article doesn't mention energy drinks at all. Isn't one of the major selling points of many energy drinks is the amount of B vitamins present? My guess is the amounts the article refers to are much higher concentrations than your average Monster / Redbull / Rockstar.

Vitamin B12 deficiency is common in people who have been vegetarian for many years. (Others usually have a large reserve.) From the speculation in the article, it sounds like they'd be better off taking (normal) doses of it, since it's deficiency or excess that could cause cancer, and not the pills:

> Deficiency can also mean genes that should be inhibited are no longer inhibited, also potentially meaning cancer. Sufficiency of certain vitamins is important in cancer prevention, but avoiding excess appears to be similarly important.

Tim Spector's book The Diet Myth: The Real Science Behind What We Eat has a chapter on B12 deficiency in vegetarians. He anecdotally found using himself as a trial that he couldn't retain B12 in blood level tests while on his usual vegetarian diet despite taking large amounts of supplements. He had to get injected B12 to get the same levels in his blood that consuming a rare steak once a month would provide. From a geneticist's viewpoint he ponders if this is some kind of trait left over from evolution. It's a good book if not 'over-written' meaning way too many flowery and very long anecdotes shoved into the research. He has a chapter on 'Vitamin supplement X causes cancer' studies as well.

By vegetarian do you mean vegan right? I have been an ovo-lacto vegetarian (commonly referred to as "vegetarian" in the US) for 15 years, have never taken any supplements, and my b12 levels are perfectly fine.

Hmm. I meant vegetarian, but upon Googling it seems that you're right that dairy and eggs contain B12. I've been vegetarian more or less my whole life but consume lots of dairy and my B12 is low. Maybe the comment sibling to yours explains it.

I'm not sure why it would be surprising that any supplement can have a bad impact on your body. If you're taking a supplement because you believe it has a potential benefit, it must have some impact on your body so therefore too little or too much must surely be bad as well?

In general terms, I agree. Since B vitamins are mostly water-soluble[1], generally it has been assumed that excess would be excreted, and research that suggests that some of them are not so harmless is news.

1: https://en.wikipedia.org/wiki/Vitamin#List_of_vitamins

The vitamin industry is scaring people to prop up sales. Eat a more or less varied diet and you'll be fine, unless you have a very specific condition (pregnant for one).

Less Vitamin X today is not going to kill you. It's probably better than, "oh I need 1000mg so I'll just take 5000 and let the body handle it."

Such a misleading headline and article, most vitamin tablets (atleast in the UK) contain no more than 1-2mg of either B1 or B12, if anything you're going to get more from eating excessive meat which is a higher risk. This study is extremely suspicious as to who funded both it and whos behind this article.

You're confusing milligrams (mg) and micrograms (mcg or µg). The recommended daily intake is a few micrograms; those tablets contain 1000 times that amount.

Definitely worth more research into possible mechanisms, but until studies account for the numerous contamination issues (lead, etc.) that many different home supplements carry, then there is going to be a mystery factor in so many of these studies sending all kinds of mixed signals.

The word excessive needs to be in the title.

In 20 years of looking I've never seen a study that links recommended daily allowance amounts to anything harmful.

Yes 1000x RDA vitamins should be banned, but incendiary titles muddy people's thinking.

The reason people take 1000x plus etc is often due to absorption issue.

Many people have problems absorbing B12. That's why they have a deficiency to begin with. In order for these people to get normal B12, it requires extreme doses just for their bodies to absorb normal amounts.

It's not just that -- there's an active and a passive pathway for absorption. The active pathway is limited to 1-2 µg per day by the quantity of "intrinsic factor" produced by the stomach even for people with no absorption disorder, but about 1% of oral B-12 can be absorbed through passive diffusion. If you're trying to remediate a deficiency, intramsucular shots or high oral doses are the correct approach.

I think there's another limitation in how much the liver can capture and process per day, and I don't know what that limit is, but it's higher. In any event, once it is processed (and after excess is eliminated), it is highly conserved in your body -- a few micrograms can last years, IIRC.

Yeah, the older you get the more likely you going to get absorption issues.

I have a feeling that a lot of these supplements are doing more harm than good. I really wish the FDA would step in and regulate the vitamin market the same way they do with normal medicine like Tylenol, etc.

There is little evidence that "a lot of supplements" are doing more harm than good. That is speculation. If you search pubmed there are thousands of studies looking at potential benefits.

However, if you are going to regulate based on real evidence of harm, then you would do the same for fast foods. There we have substantially more evidence of harm than we currently have with supplements.

Or we could decide to live in a free country and stop criminalizing what people decide to put into their bodies of their own free will. We are trending to free access to marijuana, I would find it ironic to then start restricting supplements.

seems very different from fast food in that with that you at least get a meal out of it however low quality it may be. But with supplements they are sometimes doing the exact opposite of what they're branded to do. Expecting greater health and getting cancer is different from being hungry and getting heart disease.

April 22, 1976, Cogress passed an act prohibiting the FDA from doing just this and in 1996 additional legislation resulted in vitamins being classified as food, not drugs.

The FDA has wanted to do something about this for a long time. They clearly see supplements as dangerous (especially things like 6000% RDA).

I think it would be better of the goverment just let anyone eat or take anything they want. Though they should fund extensive research into food, vitamins, home remedies, etc. and publish them in easy to understand guides and warnings. This could empower the people to protect themself.

The drug industry is actually fairly close to that model:

1. You can't advertise any benefit without having a clinical trial (funded by the company) showing that benefit.

2. A strict (every 6 months) inspection of manufacturing facilities.

3. You're required to list the ingredients, and the inspections make sure you're using them.

4. All known side effects are required (found during aforementioned clinical trials) to be listed.

By contrast, the FDA is specifically prohibited from applying these regulations to the supplement industry. Unsurprisingly, many studies have found that the companies involved don't even bother to put the active ingredients in the pills.

BigPharma would love this.

Why stop there though. I think we should require a prescription. You shouldn’t be putting stuff into your body without medical supervision.

I’d even consider it for Foods heavy in certain vitamins. Pineapples have a mega load of vitamin c. Put those behind the counter as well. Why let people risk their health.

> You shouldn’t be putting stuff into your body without medical supervision.

Neither you nor the government should be telling me what I can put in my body.

> Why let people risk their health.

Because it's their health to risk, not yours.

Sarcasm aside, I did read that over consumption of kale results in accumulation of heavy metals


Uh oh, does his mean Vegemite is bad for you!?

Seriously, most people with a western, meat-dominated diet likely get sufficient B automatically.

Wait: this was downvoted??

I can understand down voting snark and off-topic comments.

I can understand (though disagree with) down voting unpopular opinions.

But this is simply a comment (well, two comments) on sources of B vitamins in the human diet.

I know complaining of down voting is itself poor form, but really??

vegemite contains almost no B12.

no B12 but crap loads of monosodium glutamate https://en.wikipedia.org/wiki/Glutamate_flavoring

MSG is perfectly safe.

Only if referred to as "kombu" (from which it was first harvested). If you use that scary chemical name it's bad juju.

Whew! (wipes sweat from brow)

I guess I'd better stop hitting this VITAMINVAPE

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