I don't understand your insistence to include food sources that are not particularly high in B12 content by comparison to other foods on the USDA ranked list, and for your apparent belief they are common foods: mushrooms, seaweed, fermented foods? Of course, they are in the mainstream markets, but each would have a small percentage of regular users. Your content falls into WP:UNDUE which is a disqualifier for content in the lede per MOS:INTRO, Relative emphasis. Please do not edit war over this minor difference; WP:3RR as a caution. -- Zefr ( talk) 03:07, 6 April 2017 (UTC) reply

Those plant foods contain "signifiant" amounts of B12, as was the conclusion of the two citations already included (Orogen State study and their cited journal). These foods are consumed fairly frequently by people across the world, particularly in certain regions of the world where some (if not all) are among their staple foods. Frequency also is not as relevant in relation to food sources with signifiant amounts of B12 since the body utilizes low amounts at a time and retains the vitamin for long durations. Perhaps this is something that should be resolved by a wider consensus if you cannot see the reason in including such a short and relevant addition.

The 'Foods' section should also make the distinction between animal sources and plant sources (and labelled as such rather than "Foods" and "Other"). I plan on adding a 'Plant Sources' section with a more in depth description of plant foods containing B12 similar to the 'Animal Sources' section - for the sake of balancing the facts. Cyrus Freedman ( talk) 03:31, 6 April 2017 (UTC) reply

The Oregon State article on food sources here takes their data from the USDA source I provided, and does not include mushrooms, seaweed, fermented foods or spirulina. We don't have to detail all foods for the B12 article, but just provide a guide to general categories which can be summarized from the USDA ranked list as shellfish-meats-fortified foods (breakfast cereals); supplements can be added as an obvious manufactured source. Pay attention to the quantitative values for B12 content among the several hundred ranked foods, and you'll see my point. Your choices of mushrooms-seaweed-fermented foods cannot be justified from the USDA list, nor is there a solid secondary source to support those choices. Without WP:SECONDARY, your choices should not be included, as there are many others ranked higher than them. -- Zefr ( talk) 04:01, 6 April 2017 (UTC) reply

It seems you haven't read through their findings in its entirety, under the foods section here they are mentioned. "Recent analyses revealed that some plant-source foods, such as certain fermented beans and vegetables and edible algae and mushrooms, contain substantial amounts of bioactive vitamin B12". The citation that fallows here(81) goes into further detail. As said in the talk page, relying solely on the findings of one source at the expense of relevant additional sources is not in keeping with a unbiased overview, and the credibility of the USDA as a neutral source is in question since they have a long track record of being heavily lobbied by, and having a revolving door relationship with, various private industries - whereby regulators, lobbyists, investors, and CEO's transition between conflicting private/public positions.

It's difficult to make accurate comparisons for nutrient content when different investigators use different samples and methods. That's why the USDA is so highly regarded for their National Nutrient Database. Your comment about questioning their credibility is soapbox crap -- the USDA is respected worldwide. If you're going to cite other food sources, first you should find the food in the USDA list to verify the content. I bet you'll find foods with higher content if the USDA list is used. -- Zefr ( talk) 04:40, 6 April 2017 (UTC) reply

Appealing to one authority is a mistake, let alone the USDA's authority. The USDA's corruption is not a controversial concept to most institutions outside the US. In fact it's held in rather low esteem by less Plutocratic countries around the world becase of its low ethics standards regarding monied conflicts of interests. USDA aside, the cited Oregon study mentions both animal and plant sources with signifiant sources of B12 and therefore both should be included in keeping with the rules on bias (unless there's some evidence that Oregon State or its source are not reputable) Cyrus Freedman ( talk) 05:14, 6 April 2017 (UTC) reply

Z's mention of USDA as an authoritative source was specific to National Nutrient Database. Concerns - warranted or not - about other USDA content not relevant. David notMD ( talk) 13:04, 9 October 2017 (UTC) reply