10 foods to increase your vitamin B12 and your energy

Tuna
Tuna is a commonly consumed fish and great source of nutrients, including protein, vitamins, and minerals. Tuna contains high concentrations of vitamin B12, especially in the muscles right beneath the skin, which are known as dark muscles (20). A 3.5-ounce (100-gram) serving of cooked tuna contains 453% of the DV for the vitamin.