What foods are rich in Vitamin B12 (Cobalamin)?

From the Guidelines

Vitamin B12 is primarily found in animal products, with the richest sources being organ meats like liver and kidney, as well as clams, sardines, beef, tuna, salmon, and dairy products such as milk, cheese, and yogurt 1.

Key Food Sources of Vitamin B12

• Organ meats: liver and kidney
• Seafood: clams, sardines, tuna, and salmon
• Meat: beef
• Dairy products: milk, cheese, and yogurt
• Eggs: moderate amounts of B12
• Fortified foods: nutritional yeast, plant milks, breakfast cereals, and meat substitutes for vegetarians and vegans

Importance of Vitamin B12

Vitamin B12 is essential for nerve function, DNA synthesis, and red blood cell formation. The recommended daily intake for adults is 2.4 micrograms. Since B12 is water-soluble, excess amounts are generally excreted, making toxicity rare. However, those following plant-based diets, individuals over 50 with reduced absorption capacity, or those with certain digestive conditions may need supplements to maintain adequate B12 levels and prevent deficiency symptoms like fatigue, weakness, and neurological problems 1.

Special Considerations

• Vegetarians and vegans may need to rely on fortified foods or supplements to meet their daily B12 needs
• Individuals over 50 may have reduced absorption capacity and require supplements
• Those with certain digestive conditions may need to take extra precautions to ensure adequate B12 levels
• It is crucial to treat vitamin B12 deficiency immediately, especially in cases with neurological involvement, to prevent long-term damage 1

From the FDA Drug Label

Vitamin B12 is not present in foods of plant origin, but is abundant in foods of animal origin In people with normal absorption, deficiencies have been reported only in strict vegetarians who consume no products of animal origin (including no milk products or eggs). A vegetarian diet which contains no animal products (including milk products or eggs) does not supply any Vitamin B12.

Foods rich in B12 are of animal origin, including:

• Meat
• Fish
• Poultry
• Milk products
• Eggs 2 2

From the Research

Foods Rich in Vitamin B12

• Animal foods are the primary sources of vitamin B12, including:
  • Meat
  • Milk
  • Egg
  • Fish
  • Shellfish 3
• The bioavailability of vitamin B12 from these sources varies:
  • Fish meat: 42%
  • Sheep meat: 56%-89%
  • Chicken meat: 61%-66%
  • Eggs: < 9% 3
• Some plant-based foods, such as dried green and purple lavers (nori), contain substantial amounts of vitamin B12, but other edible algae may not be suitable sources 3
• Fortified breakfast cereals are a valuable source of vitamin B12, particularly for vegans and elderly people 3

Vitamin B12 Deficiency and Dietary Sources

• A diet low in animal products increases the risk of vitamin B12 deficiency 4
• The recommended adequate intake of vitamin B12 is 4.0 μg/d for adults, with higher requirements during pregnancy and lactation 4
• Infants and children from deficient mothers and elderly people are at risk for vitamin B12 deficiency 4
• Vitamin B12 deficiency can be caused by factors such as prolonged use of metformin and proton pump inhibitors 5, 6, 7

Vitamin B12 Supplementation and Deficiency Diagnosis

• Oral administration of high-dose vitamin B12 (1 to 2 mg daily) is effective in correcting deficiency, regardless of etiology 5
• Patients older than 50 years and strict vegetarians should consume foods fortified with vitamin B12 and vitamin B12 supplements 5
• Multiple analyte testing, including serum total vitamin B12, holotranscobalamin, homocysteine, and methylmalonic acid, increases sensitivity and specificity for diagnosing vitamin B12 deficiency 6