I reckon anyone interested enough in writing an article on nutrition is likely going to be confirming they own diet in the process.

While I could recommend eating animal products, I would largely dispute your use of the word, "natural," when 90% of B12 supplements produced globally are given to animals raised for food. Taking the supplement oneself is essentially just skipping the middle man (alongside cholesterol, heterocyclic amines, arachidonic acid, and so on so forth, that come along with eating animal products).

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