Studies of vitamin B12 in turnip greens

[Korn]

From http://jn.nutrition.org/cgi/reprint/67/4/623.pdf

Here's the conclusion of this old study (it's from 1958):

SUMMARY:
The presence in turnip greens of a substance with vitamin B12 activity for chicks and for Ochromonas malhamensis was demonstrated.
The possible identity of this active substance with vitamin B12 was investigated using paper electrophoresis and chromatography. By these criteria, there was no evidence that the substance in the turnip greens differed from cyanocobalamin. The fact that the vitamin B12-active material was found
in turnip greens grown at one location but not in those from another raises the question of its origin. Possible sources of this vitamin B!2 were discussed.

[horselesspaul]

Korn, that's great. I shall read it with interest (especially as the conclusions have been reached through the abuse (in 1958) of fellow beings). I love turnips now but used to hate them when I was an omni all those years ago (as with spinach, olives, watercress ..anything with miso). Another example of my purely anecdotal evidence that one's body tends to crave that which we need as well as that which we desire.

[Michael Benis]

Could they tell the difference between B12 and analogues then?

The posts about pond water etc. are also intersting. It's likely that in a less hygienic age it was difficult not to get enough B12 in the diet.

[Korn]

Could they tell the difference between B12 and analogues then?

I doubt they could - this is a link from an old article, and since almost nobody seem to document the ratio between B12 and B12 analogues today - not in plants, not in animal products, not in supplements or fortified food - or to which degree the existence of B12 analogues together with active B12 always represent a real problem, I don't think we should except to find much knowledge about these issues released back in 1958. But then again, what's the ratio between active B12 and B12 analogues in a traditional non-vegan lunch, a multivitamin pill containing B12, in 'dirt', which everybody seem to agree contains real B12, or in fortified food?

It seems that there will always be people - including vegans - who assume that all plants contain only B12 analogues, and that the presence of B12 analogues always is a problem (in plants), but who don't care about backing this up by facts or asks the suppliers of multivitamins and fortified foods to document the ratio between B12 and B12 analogues in the multivitamins they take, or ask for documentations about the amount of B12 humans can get from dirt or bugs.

I don't suggest that anyone should eat bugs, it just seems that if someone claims that we can get enough B12 from eating some chicken or eggs or bugs, nobody questions if this is true, but if someone shows figures documenting eg. that "about 36% of the total corrinoid vitamin B-12 activity in Spirulina is human active", they - even if they are vegans or not, and in spite of personally not having seen non documentation on either side - this group of people/vegans almost automatically assumes that the 'facts' that support eating animal products are always reliable.

I wonder if the vegans who trust the information from 'the other side' more than the info that supports a vegan diet are as skeptical about the information about vegans being able to get B12 from dirt or bugs or supplements as they are about information about plants containing B12...

It's likely that in a less hygienic age it was difficult not to get enough B12 in the diet.

The body contains more bacteria than cells, and exposing ourselves to all sorts of chemicals that kills both the good and bad bacteria isn't necessarily 'hygienic'. Sometimes it's just hysteria - or ignorance.

[Michael Benis]

Sorry Korn, it's the other way round. There were lots of claims about certain things (Miso, tempeh, collard greens, spirulina etc etc.) supposedly containing B12 which were found to contain analogues only and not B12. Some of course contained neither.

That's not supposition or an argument by the other side. That's a fact and it's not relevant to veganism as a "cause" because there are vegan B12 supplements.

It's simply relevant for helping people maintain a healthy diet. Anything else is unethical. Misinformation about vegans and vitamin D and in some countries iodine is also unethical. These are the few things we currently know we have to be careful of, just as we thankfully now know that the whole business about food combining for amino-acid balance that everyone obsessed about in the seventies is complete nonsense.

Cheers

Mike

[Korn]

Sorry Korn, it's the other way round. There were lots of claims about certain things (Miso, tempeh, collard greens, spirulina etc etc.) supposedly containing B12 which were found to contain analogues only and not B12.

These claims basically came from the macrobiotic movement circa 40 years ago or more, and while some parts of the vegan and macrobiotic movements still have a tendency to believe in everything they read and repeat whatever they read some decades ago, I've found that the most common way to think of B12/plants is that there is no B12 in plants, or if it is, it is always unusable B12 analogues.

It's quite common to assume the the majority is right, and since most people tend to believe that one cannot survive on a vegan diet, all facts that support this belief is true. If someone says that there actually may be usable, bioavailable B12 in plants, he is asked for proof/references to actual studies, but if someone claims that one cannot get B12 from plants, or that all B12 in all plants is unusable or even dangerous, most people (and many vegans) will just accept it blindly.

That's not supposition or an argument by the other side. That's a fact and it's not relevant to veganism as a "cause" because there are vegan B12 supplements.

That's your opinion, but for a lot of people, any diet that needs supplementation will not be even worth considering - except if the supplementation is needed due to 'external' reasons, like eg. B12 being reduced by non-natural causes. It's only fair that some people don't care if a diet or lifestyle isn't 'natural', but when communicating with others, I think it's our duty to take all these people that look at things from a different perspective into consideration.

Look at this poll: Top 50: Comments from non-vegans
The most common question vegans are asked is where they get their nutrients from. This means that it's important to inform people about both possible vegan B12 sources, not only inform about which nutrients vegans need to focus on, but also mention all the nutrients non-vegans normally have low levels of, and also inform about all the 'non-natural' factors out there that may destroy the B12 that can be found form non-animal sources.

It's simply relevant for helping people maintain a healthy diet. Anything else is unethical.

Suggesting supplementation is relevant for those who need supplementation.

Have you seen the "Nutrition: What's the best advice we can give to new/potential vegans?"-thread, Michael"? Do you agree that if we should generalize at all, the nutrient that new vegans need to worry the least about is B12, because B12 is one of the few nutrients that non-vegans have higher levels of than vegans?

Regarding the ethical aspect you mention, I think it's our duty to inform vegans about the real facts, the stuff that there's disagreement about, and not claim that something is always safe (or always risky) if this isn't the case. There's a huge amount of studies and opinions between the two extremes here, one saying that vegans never need to take supplements if they only eat varied/organic or raw food, while the other more or less claims that you need to take B12 supplements from the day you go vegan or else you will die or experience neurological disorders. A lot of plain nonsense is posted from believers in both of these extreme viewpoint.

Misinformation about vegans and vitamin D and in some countries iodine is also unethical.

I think all misinformation is unethical, my point is that if we shall inform potential vegans about vegan nutrition, it's not a good idea to mention the nutrients vegans need to pay attention to in a way that gives the false impression that vegans need to worry more about deficiencies than non-vegans. As we know, nutrient deficiencies are very common among non-vegans. Vitamin D is important, and iodine is very important if you eat food from iodine-deficient soil (or for meat eaters: if you eat meat from animals that got their nutrients from iodine-deficient soil only, without iodine supplementation).

...we thankfully now know that the whole business about food combining for amino-acid balance that everyone obsessed about in the seventies is complete nonsense.

We do, but don't forget that the 'don't worry about B12, you'll get all you need from miso and tempeh'-myth also were born in the same seventies (and sixties). Most sites who inform about eg. miso today claim that miso has no or very low B12 levels, or that all the B12 in miso is 'analogues'.

There were lots of claims about certain things (Miso, tempeh, collard greens, spirulina etc etc.) supposedly containing B12 which were found to contain analogues only and not B12. Some of course contained neither.

As you may have noticed, I'm trying to collect as much info as possible about the B12 topic, so if you come across the actual studies that confirm the B12 levels and B12/B12 analogue-ratio for miso, tempeh, collard greens and spirulina, please don't hesitate about posting the info here!

We should be as scientific as we possible can - but is there really any reason to not mention the plants that are said to contain genuine B12, or to claim that no plants contain B12 when many plants actually contain B12 (most plants have never been tested, because most people rely on animal products for B12), or to feed myths created by meat-eaters that are not backed up by documentation at all (a la 'the only B12 vegans get is from the bugs living on the surface of the plants or from insect droppings')? Is there any reason to claim that you are safe if you eat supplements if thousands of vegans (and others) have a lifestyle that suggest a much higher than average B12 supplementation? Is there a reason to mention the B12 analogue issue when discussing B12 in plants only, but not mention that B12 analogues are found in standard, non-vegan animal food, multivitamins and fortified food as well? Does it make sense to recommend vegan parents to give small children more than 500-1000% of the RDA for B12? B12 recommendations are based on body weight, so why shall a kid weighing a few kilos eat approx. twice the amount of the RDA for pregnant/lactating, adult women weighing many times as much? Does it make sense to NOT inform about findings like these?

Lets try to make sense, check our facts and realize that an assumption is only an assumption - without throwing the baby out with the bath water.