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Stores of B12 can last for up to a year. Foods high in Vitamin B12 include shellfish, liver, fish, crab, fortified soy products (tofu, soymilk), fortified cereals, red meat, low fat dairy, cheese, and eggs.
Salmon, rockfish, trout, haddock and herring are some of the best fish choices when it comes to boosting vitamin B-12 intake. A 3-ounce serving of cooked salmon provides 80 percent of the recommended daily intake of vitamin B-12, while a similar-sized serving of trout provides 90 percent of the RDA.