Vitamin B12 cannot be made naturally in the body, which is why you must get enough of it from the foods you eat.
Some of the best sources of vitamin B12 include beef, pork, ham, poultry, lamb, shellfish, crab, dairy products like milk, cheese and yogurt and eggs. Fortified cereals can also provide you with sufficient levels of this vital nutrient.
Those who are vegans and vegetarians can consult their doctors and nutritionists and discuss proper supplementation alternatives for the same.