You quote a fast food company blog? I'll quote the Vegan Society:
> Claimed sources of B12 that have been shown through direct studies of vegans to be inadequate include human gut bacteria, spirulina, dried nori, barley grass and most other seaweeds. Several studies of raw food vegans have shown that raw food offers no special protection.
> Reports that B12 has been measured in a food are not enough to qualify that food as a reliable B12 source. It is difficult to distinguish true B12 from analogues that can disrupt B12 metabolism. Even if true B12 is present in a food, it may be rendered ineffective if analogues are present in comparable amounts to the true B12. There is only one reliable test for a B12 source - does it consistently prevent and correct deficiency? Anyone proposing a particular food as a B12 source should be challenged to present such evidence.
And also wikipedia which is more reliable and is not trying to sell you anything:
The Academy of Nutrition and Dietetics considers plant and algae sources "unreliable", stating that vegans should turn to fortified foods and supplements instead.[32]
Please check your sources. Such advice can be, and in fact is, dangerous to vegans.
Legumes or sprouts are not an adequate source of B12 and neither are other plant sources.
Your assertion that Nori has B12 is downright wrong.
B12 is only synthesized by microorganisms.
There are plenty of vegetarian options, but if you are vegan, you have to rely on fortified products and supplements.
This has nothing do to with where you happen to live.
You can check recommendations from physicians, researchers and most importantly Vegan associations all across the globe to the see this is true.
“The Vegetarian Resource Group (VRG) suggests that vegans need to have reliable sources of vitamin B12 in their diets. (1) The Vegetarian Nutrition Dietetic Practice Group (VNDPG) of the Academy of Nutrition and Dietetics says that all vegetarians (including vegans) should include a reliable B12 source in their diets, such as fortified foods or supplements. (2) And The Vegan Society goes so far as to state, “What every vegan should know about B12: the only reliable sources of B12 are foods fortified with B12 and supplements.” (3)“
I have seen people get sick ignoring these issues in a vegan diet.
“According to vegan expert and co-author of Vegan for Life, Jack Norris, RD, there are no reliable sources of B12 in plants, contrary to many rumors about sources, such as tempeh, seaweeds, and organic produce. Plants have no B12 requirement, therefore they do not have any active mechanisms to make or store it. When you find B12 in plants, it is due to contamination, which is not a reliable source. Many seaweeds have B12 analogues, through their symbiotic relationship with cobalamin-producing bacteria, however the evidence is not clear that this form is active B12 in humans. And fermented foods, such as tempeh, are not fermented through B12-producing bacteria, thus they are not a source of B12. Rumors about bacteria on the surface of organic produce producing B12 have not been verified. “Chlorella may improve B12 status, but it’s by such a small amount that I wouldn’t rely on chlorella for B12,” adds Norris. Norris stresses that, unless a food obtained from multiple regions consistently improves B12 status, it should not be relied upon as a source of B12.“
A vegan diet can be a healthy and sensible choice for people living in a modern society with access to supplements and fortified foods as well as the care and knowledge to use them. Otherwise it is not an appropriate diet for humans, especially not outside of the modern Western organic supermarket and supplement infrastructure.
>When it's found in "soil", it's due to bacteria and small animals (insects, mites) that are in the soil.
I'm not sure what your point is.
>Any B12(-like) substances that are in plants (e.g., spirulina) are unlikely to be in a form that's bioavailable to human beings.
Yes, this is true.
>Vegans have to take B12 supplements of some sort or eat foods that have been fortified with B12. That's just a fact.
Modern vegans do need to take supplements, yes. The question is whether vegans in the ancestral environment would have gotten sufficient B12 from eating unwashed vegetables and roots. As far as I know, research is lacking on that point, but it is plausible.
They are completely wrong. There is some b12 generated by our gut bacteria but it is too low in the digestive track to be effectively absorbed. There is a reason vegans eat foods enriched in b vitamins.
"I've never heard of a study claiming B12 in animals in vivo is not synthesized by bacteria (or archaea). Care to give a reference?"
That's not what I was referring to. I'm referring to the (implied) claim that the B12 synthisized in our gut by bacteria is available to us.
Wikipedia doesn't support that claim, and Wikipedia is editable by anybody, so while it's mostly trustworthy, if a heavy portion of the editors have a bias, it's going to show in an article that is heavyily political/quasi-relisious like veganism. Or vice versa if Wikipedia editors are heavily carnivorous (e.g Atkins) and hate vegans or something like that.
"Been vegetarian for over 35 years (only a few years of those vegan, but not having a B12 source in almost any)."
Well, I don't know you, and can only assume you aren't lying or bending the truth, so I'll say that it is possible you are an outlier. In a cursory search yesterday (a couple hours only) I found references on both sides of the fence claiming that we can use B12 synthisized in our gut, and about the same number of sources saying we couldn't.
Who to believe in such a hot, political topic. A guy with an axe to grind (vegan trying to defend/promote his lifestyle) or the fact that there seems to be no concensious in the sciencific community?
iirc, that's not quite right. All dietary B12 originates in/on plant sources, you just have to avoid processing that removes it, and include plant sources with good sources. If you try and eat vegan from a typical north american grocery store though, you may have trouble and need to supplement it. On the other hand, selections are pretty good these days, and if you incorporate some nori or legume sprouts (from memory) you'll be fine.
> Vitamin B12 deficiency in the US and the UK is estimated to occur in about 6 percent of those under the age of 60, and 20 percent of those over the age of 60.[1] In Latin America rates are estimated at 40 percent and they may be as high as 80 per cent in parts of Africa and Asia.[1]
It's not true that "you cannot get B12 from plants, period" [1]. You can get trace amounts from various edible land plants, but dietarily significant quantities from some algae. Also fermentation of some plants can provide B12-rich foods.
It's fair to say that vegans need to take particular care that they get sufficient B12.
Ctrl+F "B12". Here's a quoted reference from the article:
> [V]egans exhibited a higher estimated prevalence of inadequacies for some nutrients, in particular vitamin B12 (69.9% in men and 83.4% in women <55 years of age), compared to meat-eaters. […] Our study highlighted that, overall, self-reported vegetarians and vegans may meet nutritional recommendations.
Those numbers are crazy high. I am not an expert in any of this, so take this with a healthy dose of skepticism, but I wonder if a vegan diet can be considered healthy without supplements given the current range of available non-animal B12 sources. I think there are some algae sources but I'm not sure you can get enough B12 without getting too much of something else. There's also the question of how efficiently you absorb the nutrients in the food; I heard it's harder to absorb B12 from algae than from cheese for example. Happy to be shown evidence for or against...
Who's misdirecting? You still haven't cited anything. I'll play along though; which nutrient(s) can only be obtained from animal sources? Even B12 is only accumulated in animal tissue, it's not produced by animals.
Anecdotally, I've been following a thoughtful vegan diet with B12 supplementation for 8 years. The results of my last blood test (including tests for various likely deficiencies) were exemplary. Could you post something other than your opinion? Otherwise, I'm done here.
I don't need to cite anything, 10 seconds on google scholar looking for long term studies will suffice for your needs.
Good luck with it and be careful.
tl;dr
Here's your 100 day challenge, get 100% of your dietary requirements from your diet (without fortification of key ingredients or supplements, just from pure foodstuffs), and prove to me that you aren't eating a poor diet.
here's the tl part:
You're overfocusing on B12, because the literature on vegan nutrition overfocuses on B12 as neurological damage caused by B12 deficiencies are generally irreversible. Dietary B12 doesn't come from many non-animal sources, but you don't need much anyway, and effects of B12 deficiencies aren't symptomatic for several years. Your pre-vegan intake of B12 would have been sufficient for a few years until you figured out non-animal sources of it. It's also unclear to date if the form of B12 found in non-animal sources (synthetic eukaryotic sources, etc.) functions identically to animal sourced (from prokaryotic sources) B12. There are almost no studies on it because you have to try and be deficient in B12 on a normal diet without large-scale intestinal disorders.
"Even B12 is only accumulated in animal tissue, it's not produced by animals."
I don't think you understand where B12 comes from, I'm sure your understanding came from some vegan promotional literature which seems woefully full of cherry picked misunderstandings and absurd apologetics.
I'm sure you're getting it through some supplement. Now get it through dietary means. Or if you actually care about the environment, get it from locally produced dietary sources alone and don't have to have some heavily processed fermented foodstuff shipped a thousand miles to your fridge. I don't need to cite anything for you to know you simply can't.
a-linolenic acid is where you'll probably have the biggest long-term health issues, as metabolism into EPA and DHA is very inefficient with most of the issues in DHA production. Multiple studies show deficiencies in vegan diets w/r to DHA. Synthesis, requires several dietary co-factors in careful balance and long term studies suggest possible liver damage in humans (but not conclusively) vs. simply ingesting animal sources of long-chain n–3 fatty acids. Most vegans eat sources of ALA thinking it will makeup for their dietary deficiencies EPA and DHA, but multiple studies show that DHA levels remain deficient in these cases.
I'm sure you take supplements to make up for this inadequacy in your diet. Now do it without them. And if you think that your non-animal sourced Omega-3 supplement is complete, think again. There is no such thing as one kind of ?-3. You need them all, but in particular you need EPA and DHA.
Oh and DHA supplements also have a nasty side effect of preventing blood clotting, damaging immune response and increasing LDL levels. In other words, don't take them, they will hurt you.
Vitamin D should also be a no-supplement required vitamin. You make it in your skin for goodness sakes! It's not really essential, but it's plentiful in animal sources, and just stepping out in the sun for a bit everyday is more than sufficient to produce all the D secosteroid you could ever possibly need. If you feel the need to take D supplements, for all that is holy, take D3 and not D2 as the bio-availability of D3 is several times higher than D2. But of course, if you're taking "vegan-friendly" D supplements, it's almost always a fungal source which of course is the deficient D2 ergocalciferol form. I would suggest UV lamps at your desk instead of supplements.
I'm sure you already know about Iron and Zinc deficiencies in your diet. Every vegan I know is acutely aware of it and tries to eat lots of iron and zinc rich food stuffs and takes yet again more supplements to make up for their shitty diet.
But look, the point is this: the definition of a poor diet is a diet that doesn't provide for all of the necessary nutrients as part of the diet. If you have to take supplements to make up for dietary shortfalls, your diet is a poor one...period. Waiving away the handful of supplements you take everyday is madness and a serious problem.
Vegans are among the only otherwise healthy population group in the developed world that routinely suffers from illnesses seen only in the most decrepit poverty stricken parts of the undeveloped world. Most vegans source their information from highly biased vegan promotional material and don't understand the basic science.
I get it, you want to help the animals out of some sort of moral obligation. And I'm sure you only eat food produced on farms with no field kills, and use the parts of the internet only on a machine powered by sources that have no animal impact. And that somehow you live in a vegan mecca where somehow all of the various plants that produce 100% of your dietary requirements don't have to be shipped from halfway around the planet killing goodness knows how many animals in the process and that you believe in a world where everybody else goes vegan and the billions of domesticated farm animals somehow continue to find sponsorship for their care and maintenance in perpetuity. I think that's great.
Just be careful, and proceed with the understanding that long-term, you won't be able to sustain this diet without compromises to your health.
> Every statement you've made, every single thing you've just written, is provably false.
No, they're not.
> Most vegans will need an actual B12 supplement.
It obviously depends on how much of any given fortified B12 food you consume. Hypothetically yes, you could eat enough fortified foods to avoid the need for a pill, but it'd take a lot more intentional eating on the vegan's part. Most vegans should take a B12 supplement because it ensures that they're getting enough B12, while fortified foods have varied amounts of it.
> This is true, except that people don't eat algae, so it's an additional supplement you need to take.
I take this back, people do eat nori which is algae. It just doesn't contain vitamin d. Vegan would take a supplement, since vitamin D is not prevalent inside of plants. Another option might be UV-exposed mushrooms, but generally you either need fortified foods or a supplement. Vegan vitamin d supplements are produced from the algae you mentioned.
> All of which have low bioavailability which is why so many vegans have iron anemia. In fact eating mostly fibrous plants and seeds likely inhibits iron uptake.
Plant sources of iron do not contain heme iron, they contain non-heme iron, which is less bioavailable. 25% of heme iron and 17% of nonheme iron get absorbed, which seems insignificant until you realize exactly what that translates to in terms of how much material you need to consume to reach that.
The only source of 1300 mg claim that i saw was webmd... which is what you copied that sentence from.
> The phytates and oxalates in those inhibits calcium's bioavailability in these foods. You get it from supplements, once again.
Phytates play a larger role than oxalates. It's the same issue as with iron. Phytates bind with calcium which can prevent uptake.
Stop making impassioned statements trying to push an agenda you're unwilling to defend. My argument is defensible. It's quite possible I'm wrong about some of it, but it's certainly not driven by dogma.
> you too, are likely to be running a vitamin B12 deficiency
Citation please? I've looked into this subject pretty intensely over the last decade or so and know of no controlled studies (or even poorly done observational studies) that demonstrate this in the least. The only place I've ever even seen this claim is on vegan advocacy forums as unsubstantiated claims or in studies of nutrition absorption problems as a general factor in the elderly. The amount of animal meat needed for full dietary B12 is actually shockingly small. A few grams a week. And it's water soluble so you just piss out any that's not used.
On the contrary I've read several studies that show that in the study populations, up to 92% of the vegans in the population were B12 deficient.
In another a little over 50% of vegans were deficient, while less than 10% of vegetarians and a single omnivore were B12 deficient.
I know of no studies where the studied, randomly sampled, vegan population was not majority B12 deficient.
In other studies that look for it, elevated methylmalonic acid (associated with B12 deficiency) was found in the vast majority (over 80%) of vegans while only 5% of ominivores and 68% of vegetarians. In the same study almost 70% of vegans were diagnosed with Hyperhomocysteinemia (caused by sustained deficiencies in B-vitamin groups or chronic alcoholism) while less than 20% of the omnivores were.
The most effective and reliable treatment for Hyperhomocysteinemia is a regular omnivorous diet of meat and eggs with a cure rate of nearly 100%.
> Last I checked, unless vegans are supplementing their diets with multivitamins, they lack all the necessary nutrients needed to survive.
Source? I've been vegan for close to three years now and don't take multivitamins, yet I'm surviving. So long as you eat a variety of foods (and if you're female, plenty of leafy greens) you're all set.
There is however exactly one vitamin which is not available from plant-based sources, and that is B12. However it is produced by bacteria and thus is may be cultured as a supplement.
Please check your facts before posting next time and stop spreading misinformation.
> The usual dietary sources of vitamin B(12) are animal foods, meat, milk, egg, fish, and shellfish. As the intrinsic factor-mediated intestinal absorption system is estimated to be saturated at about 1.5-2.0 microg per meal under physiologic conditions, vitamin B(12) bioavailability significantly decreases with increasing intake of vitamin B(12) per meal. The bioavailability of vitamin B(12) in healthy humans from fish meat, sheep meat, and chicken meat averaged 42%, 56%-89%, and 61%-66%, respectively. Vitamin B(12) in eggs seems to be poorly absorbed (< 9%) relative to other animal food products. In the Dietary Reference Intakes in the United States and Japan, it is assumed that 50% of dietary vitamin B(12) is absorbed by healthy adults with normal gastro-intestinal function. Some plant foods, dried green and purple lavers (nori) contain substantial amounts of vitamin B(12), although other edible algae contained none or only traces of vitamin B(12). Most of the edible blue-green algae (cyanobacteria) used for human supplements predominantly contain pseudovitamin B(12), which is inactive in humans. The edible cyanobacteria are not suitable for use as vitamin B(12) sources, especially in vegans. Fortified breakfast cereals are a particularly valuable source of vitamin B(12) for vegans and elderly people. Production of some vitamin B(12)-enriched vegetables is also being devised.[1]
So it seems like that despite them containing substantial amounts of vitamin B12, they are not suitable for use as vitamin B12 sources because they predominantly contain pseudovitamin B12 which is inactive in humans. They recommend fortified breakfast cereals for vegans.
What you said about cats inability to digest plants is of no significance here. Vitamin deficiency - especially this particular one - is life-threatening. We need it. We can definitely have plants, and we may need plants as well, but we do need to eat something that contains substantial amounts of non-pseudovitamin B12, which is meat. Of course you can just be a vegan and supplement vitamin B12, but...
I'd have to spend more time than I have hunting the relevant studies down. I don't even pretend to understand most of the fundamental science, but my very cursory studies show that long-term vegan diets are pretty much a terrible idea for humans, despite what vegan advocacy literature proclaims, there are no populations of humans on the planet that go for a lifetime (or generations) on a purely vegan diet. Most of the ones used as examples, have some animal sources in their diet but those sources are not recorded or well understood by outside observers who are also biased by trying to advocate for a particularly philosophical dietary proscription.
Just with respect to the B group vitamins, there's quite a few studies of vegan populations that show a consistent deficit in B12. Depending on the study, vegan populations consistently show (at 70-90% of the studied population) B12 deficits, even while taking supplements. The general conclusion among nutritionists is that it's very very hard for vegans to get enough B12 in their diets no matter what they try. Strangely, these studies never seem to show up in Vegan advocacy circles or support groups, though there is a general awareness that B12 availability is a problem with the diet. More problematic, B12 deficiency (and the related issues below) do not present as immediate health issues, but develop over years and decades - presenting as permanent damage to neurological tissues. People who switch to Vegan diets often don't present with this deficiency for several years as the liver maintains a 3-5 year store of the vitamin.
B12 deficiency can be fatal. B12 deficiency is trivially treated by eating meat - surprisingly little meat too. Similar studies of Vegetarian populations who occasionally eat some animal source, don't show nearly as frequent B12 deficiencies as in Vegan populations.
Identifying B12 deficiency can be difficult as normal assays don't reliably show deficiencies, and initial symptoms looks like anemia, which is also highly prevalent among vegan dieters and may co-present.
Along with B12 deficiency, elevated methylmalonic acid is typical in some majority of the studied vegan populations. Which is used as a secondary signal to confirm B12 deficiency. MMA reacts with B12 to produce coenzyme A (CoA) which is necessary for normal cell function. People with elevated MMA are often diagnosed with methylmalonic acidemia - a group of disorders which are normally only seen in infants with specific genetic conditions relevant to B12 absorption, but present with progressive encephalopathy and hyperammonemia, both can cause death over the long-term.
A majority of vegans can also usually be diagnosed with Hyperhomocysteinemia (which is only ever seen in three population groups, the severely malnourished, the extreme elderly and vegans and is trivially treated with an omnivorous diet). Studies which show cardiovascular issues in Vegans (surprisingly more common than you'd think) attribute them to Hyperhomocysteinemia as Homocysteine prevents proper formation and maintenance of key cardiovascular components like collagen and elastin (also noticeable in Vegan populations as "thin skin" or "premature wrinkling"). It's also linked to Alzheimer's disease and Schizophrenia. The later disease occurs in vegan populations with a startlingly higher frequency than in vegetarian and omnivorous dieter populations.
This is just some of the issues from B12 deficiency, which occurs somewhere between 70-90% of any randomly selected vegan population. So we know that vegans, as a general population, are not able to supply themselves with sufficient B12.
You can probably google for the relevant studies on your own. There's plenty of them around, but I'd urge you to find them in medical journals, not interpreted through vegan advocacy sites which seem to have a habit of ignoring the important health issues and suppressing negative health outcomes from the diet.
I'd urge you to check out amino acids, and fatty acid issues as well, as they are just as common in vegan populations and can be just as health concerning.
Interestingly, almost every single health issue that stems from a vegan diet is trivially treated by just eating a few grams of animal protein sources a week. Eating plant foods or supplements rich in these normally vegan deficient nutrients doesn't mean they're bioavailable, what matters is absorption of the relevant nutrient, which is something that vegan diets are notoriously poor in providing.
> and the missing nutrients can be acquired even on a plant-based diet.
Vitamin B12 is a notable exception - there are no plant-based foods which are a significant (or reliable!) B12 source that I'm aware of. Other B vitamins: yes. B12: no. Vegans should either supplement, or (possibly after a looong time) will develop a chronic shortage.
Calcium (not mentioned in the article) is another one. Many plant-based 'milks' are fortified with it. But if not (or people not drinking these regularly) getting enough calcium from a plant-based diet is tricky.
There are other ones to keep an eye on (iron comes to mind) but usually less of an issue.
Vegetarians and vegans, hope you have (or will have) carefully reviewed the available medical information about what are reliable sources of B12, how to get sufficient amounts, and consequences of not getting enough. Years ago I went low on B12, now I consistently supplement. Be safe.
https://www.mayoclinic.org/drugs-supplements-vitamin-b12/art...
"However, if you follow a vegetarian or vegan diet, you might be prone to deficiency because plant foods don't contain vitamin B-12. "
https://veganhealth.org/vitamin-b12/
"Vitamin B12 is generally found in all animal foods except honey while there is no reliable B12 in plant foods, including tempeh, seaweeds, and organic produce. "
https://veganhealth.org/vitamin-b12-vegan-sources/
"Brewer’s and nutritional yeasts do not contain B12 unless they are fortified with it. "
> Claimed sources of B12 that have been shown through direct studies of vegans to be inadequate include human gut bacteria, spirulina, dried nori, barley grass and most other seaweeds. Several studies of raw food vegans have shown that raw food offers no special protection.
> Reports that B12 has been measured in a food are not enough to qualify that food as a reliable B12 source. It is difficult to distinguish true B12 from analogues that can disrupt B12 metabolism. Even if true B12 is present in a food, it may be rendered ineffective if analogues are present in comparable amounts to the true B12. There is only one reliable test for a B12 source - does it consistently prevent and correct deficiency? Anyone proposing a particular food as a B12 source should be challenged to present such evidence.
https://www.vegansociety.com/resources/nutrition-and-health/...
And also wikipedia which is more reliable and is not trying to sell you anything:
The Academy of Nutrition and Dietetics considers plant and algae sources "unreliable", stating that vegans should turn to fortified foods and supplements instead.[32]
https://en.wikipedia.org/wiki/Vitamin_B12#Plants_and_algae
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