The style of diet that you choose can have an major impact on your B12 nourishment. If you regularly consume land animal foods and fish in your meal plan, B12 intake is not very likely to be a problem. If you regularly consume fish but avoid land animal foods, B12 is still relatively unlikely to be a problem. With no fish or land animal foods in your routine diet, however, you are left with some fairly specific food sources of B12, namely, fermented foods such as tempeh and fungi (including mushrooms).
We list eight excellent sources of vitamin B12 on the list of World's Healthiest Foods, which include sardines, salmon, tuna, cod, grass-fed lamb, scallops, and shrimp. We also have three very good and four good sources of the vitamin. Although the number of good sources is smaller than for many foods, this should be plenty to ensure a strong supply of this critical nutrient.